@misc{LazarevaKovalMuelleretal., author = {Lazareva, I. and Koval, Yuri and M{\"u}ller, P. and M{\"u}ller, Klaus and Henkel, Karsten and Schmeißer, Dieter}, title = {Interface screening and imprint in pol(vinylidene fluoride/trifluoroethylene) ferroelectric field effect transistors}, language = {en} } @misc{MuellerTorgerAllertzetal., author = {M{\"u}ller, Felix and Torger, Bernhard and Allertz, Peter J. and J{\"a}hnichen, Klaus and Keßler, Stefan and M{\"u}ller, Martin and Simon, Frank and Salchert, Katrin and M{\"a}urer, Haike and Pospiech, Doris}, title = {Multifunctional crosslinkable itaconic acid copolymers for enzyme immobilization}, series = {European Polymer Journal}, volume = {102}, journal = {European Polymer Journal}, doi = {10.1016/j.eurpolymj.2018.03.014}, pages = {47 -- 55}, abstract = {UV-Crosslinkable itaconic copolymers are developed to provide new multifunctional materials for coatings which combine crosslinkable functionalities and the possibility to immobilize enzymes. The polymer-immobilized enzymes were used for water treatment to decompose persistent organic molecules. Introduction of suitable comonomers allows tailoring the mechanical and chemical properties for special applications. Copolymers containing MMA and itaconic anhydride were chosen because of the formation of long-term stable anhydride functionalities. These anhydride functionalities are employed to attach enzymes covalently. 4-Benzoylphenyl methacrylate is used as comonomer for UV-initiated crosslinking. Terpolymers are successfully obtained by radical copolymerization in solution. The copolymers are compared to poly(ethylene-alt-maleic anhydride) [P(EMA)] often used with respect to enzyme immobilization, activity and hydrolytic stability. The hydrolysis stability of the copolymers against water is studied by ATR-FTIR spectroscopy. Thin films are prepared on glass substrates in a layer-by-layer procedure by spin-coating. The layer formation is monitored by ATR-FTIR spectroscopy. UV-crosslinking of the copolymer films is performed taking the optimal irradiation dose that avoids polymer degradation. ATR-FTIR spectroscopy verifies the coupling reaction between amino groups of the enzyme and the anhydride groups on the surface of the crosslinked polymer film. The syringaldazine (4-hydroxy-3,5-dimethoxybenzaldehyde azine) test and 2,2´-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assay demonstrate that the immobilized enzymes maintain their activities. The functional copolymers showed a significant effect in reduction of persistent organic pollutants in contaminated waste water.}, language = {de} } @misc{KovalLazarevaMuelleretal., author = {Koval, Yuri and Lazareva, I. and M{\"u}ller, P. and M{\"u}ller, Klaus and Henkel, Karsten and Friedrich, Daniel}, title = {Field effect transistors on graphitized polymer surfaces}, language = {en} } @inproceedings{SchmeisserMuellerHenkeletal., author = {Schmeißer, Dieter and M{\"u}ller, Sebastian and Henkel, Karsten and M{\"u}ller, Klaus and Wehner, Stefan}, title = {In-situ analysis of moving reaction fronts for the bistable CO oxidation reaction on noble metal catalyst}, series = {Extended Abstracts Book of First International Conference on Materials for Energy}, booktitle = {Extended Abstracts Book of First International Conference on Materials for Energy}, publisher = {Dechema e.V.}, address = {Frankfurt}, isbn = {978-3-89746-117-8}, pages = {S. 932}, abstract = {Experimental data on the reaction kinetics of catalytic processes are prerequisite for modeling of such reactions and their output. We investigate the CO oxidation on some noble metal catalysts, like Iridium(111) and Palladium(111) which is a bistable surface reaction. In a specific range of CO content in the feed gas islands of one or the other adsorbate nucleate and grow, which is recorded with photo electron emission microscopy (PEEM). During these transients the coverage on the surface changes from predominantly oxygen covered to predominantly CO covered resp. vice versa. But the resolution of PEEM and especially its unknown and nonlinear dependence of coverage of the two adsorbates (oxygen and CO) and image intensity make it impossible to extract the changes in coverage. On the other hand the reaction diffusion model based on the Langmuir-Hinshelwood-mechanism delivers the coverage of oxygen and carbon monoxide. The shapeand wall velocity of those islands has been connected perfectly to each other [CPL 423 (2006) 39], but not the absolute coverage and their variation during the reaction. Since the domain wall velocity is small on Iridium(111), this has opened the possibility for a detailed analysis of the changing coverage inside this domain wallutilizing synchrotron radiation and photo electron spectroscopy at BESSY II. The coverage profile of oxygen and CO inside a moving domain wall was measured for both cases using XPS spectra at O1s, C1s and the valence band during thereaction. Comparison with the reaction-diffusion-model and other catalytic surfaces, like Palladium(111) are done.}, language = {en} } @misc{HenkelLazarevaMandaletal., author = {Henkel, Karsten and Lazareva, I. and Mandal, Dipankar and Paloumpa, Ioanna and M{\"u}ller, Klaus and Koval, Yuri and M{\"u}ller, P. and Schmeißer, Dieter}, title = {Electrical investigations on metal/ferroelectric/insulator/semiconductor structures using Poly[vinylidene fluoride trifluoroethylene] as ferroelectric layer for organic nonvolatile memory applications}, language = {en} } @inproceedings{LazarevaKovalMuelleretal., author = {Lazareva, I. and Koval, Yuri and M{\"u}ller, P. and Paloumpa, Ioanna and M{\"u}ller, Klaus and Schmeißer, Dieter}, title = {Field effect transistor of graphitized polyimide with P(VDF-TrFE) as gate insulator}, series = {Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 43}, booktitle = {Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 43}, publisher = {Deutsche Physikalische Gesellschaft}, address = {Bad Honnef}, issn = {0420-0195}, pages = {S. 195}, abstract = {Surfaces of polyimide films were graphitized by low-energy ion irradiation. The conductivity was between 10-5 to 200 S/cm [1]. We prepared field effect transistors using this material. Ferroelectric P(VDF-TrFE) was used as gate insulator. The thickness of P(VDF-TrFE) varied from 120 nm to 1200 nm. Properties of P(VDF-TrFE) were investigated by current-voltage measurements of metal/ P(VDF-TrFE)/metal capacitors. We have found that at room temperature, the coercive field of P(VDF-TrFE) does not depend on the film thickness. At lower temperatures the coercive field increases proportionally to the reciprocal temperature. Remnant polarization is 9.5 µC/cm2. It slightly rises with decreasing temperature. Our recent results of field effect mobility, carrier concentration and threshold voltage are presented. [1] I. Lazareva, Y. Koval, M. Alam, S. Str{\"o}msd{\"o}rfer, P. M{\"u}ller, Appl. Phys. Lett. 90, 262108 (2007)}, language = {en} } @misc{NeyretLeProvostBoesingetal., author = {Neyret, Margot and Le Provost, Ga{\"e}tane and Boesing, Andrea Larissa and Schneider, Florian D. and Baulechner, Dennis and Bergmann, Joana and Vries, Franciska T. de and Fiore-Donno, Anna Maria and Geisen, Stefan and Goldmann, Kezia and Merges, Anna and Saifutdinov, Ruslan A. and Simons, Nadja K. and Tobias, Joseph A. and Zaitsev, Andrey S. and Gossner, Martin M. and Jung, Kirsten and Kandeler, Ellen and Krauss, Jochen and Penone, Caterina and Schloter, Michael and Schulz, Stefanie and Staab, Michael and Wolters, Volkmar and Apostolakis, Antonios and Birkhofer, Klaus and Boch, Steffen and Boeddinghaus, Runa S. and Bolliger, Ralph and Bonkowski, Michael and Buscot, Fran{\c{c}}ois and Dumack, Kenneth and Fischer, Markus and Gan, Huei Ying and Heinze, Johannes and H{\"o}lzel, Norbert and John, Katharina and Klaus, Valentin H. and Kleinebecker, Till and Marhan, Sven and M{\"u}ller, J{\"o}rg and Renner, Swen C. and Rillig, Matthias C. and Schenk, No{\"e}lle V. and Sch{\"o}ning, Ingo and Schrumpf, Marion and Seibold, Sebastian and Socher, Stephanie A. and Solly, Emily F. and Teuscher, Miriam and Kleunen, Mark van and Wubet, Tesfaye and Manning, Peter}, title = {A slow-fast trait continuum at the whole community level in relation to land-use intensification}, series = {Nature Communications}, volume = {15}, journal = {Nature Communications}, number = {1}, issn = {2041-1723}, doi = {10.1038/s41467-024-45113-5}, abstract = {AbstractOrganismal functional strategies form a continuum from slow- to fast-growing organisms, in response to common drivers such as resource availability and disturbance. However, whether there is synchronisation of these strategies at the entire community level is unclear. Here, we combine trait data for 2800 above- and belowground taxa from 14 trophic guilds spanning a disturbance and resource availability gradient in German grasslands. The results indicate that most guilds consistently respond to these drivers through both direct and trophically mediated effects, resulting in a 'slow-fast' axis at the level of the entire community. Using 15 indicators of carbon and nutrient fluxes, biomass production and decomposition, we also show that fast trait communities are associated with faster rates of ecosystem functioning. These findings demonstrate that 'slow' and 'fast' strategies can be manifested at the level of whole communities, opening new avenues of ecosystem-level functional classification.}, language = {en} } @misc{BochAllanBirkhoferetal., author = {Boch, Steffen and Allan, Eric and Birkhofer, Klaus and Bossdorf, Oliver and Bl{\"u}thgen, Nico and Christ-Breulmann, Sabina and Diek{\"o}tter, Tim and Dormann, Carsten F. and Gossner, Martin M. and Hallmann, Christine and Hemp, Andreas and H{\"o}lzel, Norbert and Jung, Kirsten and Klaus, Valentin H. and Klein, Alexandra M. and Kleinebecker, Till and Lange, Markus and M{\"u}ller, J{\"o}rg and Nacke, Heiko and Prati, Daniel and Renner, Swen C. and Rothenw{\"o}hrer, Christoph and Schall, Peter and Schulze, Ernst-Detlef and Socher, Stephanie A. and Tscharntke, Teja and T{\"u}rke, Manfred and Weiner, Christiane N. and Weisser, Wolfgang W. and Westphal, Catrin and Wolters, Volkmar and Wubet, Tesfaye and Fischer, Markus}, title = {Extensive und j{\"a}hrlich wechselnde Nutzungsintensit{\"a}t f{\"o}rdert den Artenreichtum im Gr{\"u}nland}, series = {ANLIEGEN NATUR}, volume = {38}, journal = {ANLIEGEN NATUR}, number = {1}, issn = {1864-0729}, pages = {86 -- 95}, language = {de} } @misc{MuellerPaloumpaHenkeletal., author = {M{\"u}ller, Klaus and Paloumpa, Ioanna and Henkel, Karsten and Schmeißer, Dieter}, title = {A polymer high-k dielectric insulator for organic field effect Transistors}, series = {Journal of Applied Physics}, volume = {98}, journal = {Journal of Applied Physics}, number = {5}, issn = {0021-8979}, pages = {S. 056104}, language = {en} } @misc{SchmeisserHenkelMuelleretal., author = {Schmeißer, Dieter and Henkel, Karsten and M{\"u}ller, Klaus and Tallarida, Massimo}, title = {Interface Reactions in Ultrathin Functional Dielectric Films}, language = {en} }