@article{MuellerFoerstendorfSteudtneretal.2019,
  author    = {M{\"u}ller, Katharina and Foerstendorf, Harald and Steudtner, Robin and Tsushima, Satoru and Kumke, Michael Uwe and Lef{\`e}vre, Gr{\´e}gory and Rothe, J{\"o}rg and Mason, Harris and Szab{\´o}, Zolt{\´a}n and Yang, Ping and Adam, Christian K. R. and Andr{\´e}, R{\´e}mi and Brennenstuhl, Katlen and Chiorescu, Ion and Cho, Herman M. and Creff, Ga{\"e}lle and Coppin, Fr{\´e}d{\´e}ric and Dardenne, Kathy and Den Auwer, Christophe and Drobot, Bj{\"o}rn and Eidner, Sascha and Hess, Nancy J. and Kaden, Peter and Kremleva, Alena and Kretzschmar, Jerome and Kr{\"u}ger, Sven and Platts, James A. and Panak, Petra and Polly, Robert and Powell, Brian A. and Rabung, Thomas and Redon, Roland and Reiller, Pascal E. and R{\"o}sch, Notker and Rossberg, Andr{\´e} and Scheinost, Andreas C. and Schimmelpfennig, Bernd and Schreckenbach, Georg and Skerencak-Frech, Andrej and Sladkov, Vladimir and Solari, Pier Lorenzo and Wang, Zheming and Washton, Nancy M. and Zhang, Xiaobin},
  title     = {Interdisciplinary Round-Robin Test on molecular spectroscopy of the U(VI) Acetate System},
  series = {ACS omega / American Chemical Society},
  volume    = {4},
  journal   = {ACS omega / American Chemical Society},
  number    = {5},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {2470-1343},
  doi       = {10.1021/acsomega.9b00164},
  pages     = {8167 -- 8177},
  year      = {2019},
  abstract  = {A comprehensive molecular analysis of a simple aqueous complexing system. U(VI) acetate. selected to be independently investigated by various spectroscopic (vibrational, luminescence, X-ray absorption, and nuclear magnetic resonance spectroscopy) and quantum chemical methods was achieved by an international round-robin test (RRT). Twenty laboratories from six different countries with a focus on actinide or geochemical research participated and contributed to this scientific endeavor. The outcomes of this RRT were considered on two levels of complexity: first, within each technical discipline, conformities as well as discrepancies of the results and their sources were evaluated. The raw data from the different experimental approaches were found to be generally consistent. In particular, for complex setups such as accelerator-based X-ray absorption spectroscopy, the agreement between the raw data was high. By contrast, luminescence spectroscopic data turned out to be strongly related to the chosen acquisition parameters. Second, the potentials and limitations of coupling various spectroscopic and theoretical approaches for the comprehensive study of actinide molecular complexes were assessed. Previous spectroscopic data from the literature were revised and the benchmark data on the U(VI) acetate system provided an unambiguous molecular interpretation based on the correlation of spectroscopic and theoretical results. The multimethodologic approach and the conclusions drawn address not only important aspects of actinide spectroscopy but particularly general aspects of modern molecular analytical chemistry.},
  language  = {en}
}
@article{WangKaunePerlichetal.2010,
  author    = {Wang, Weijia and Kaune, Gunar and Perlich, Jan and Paradakis, Christine M. and Bivigou Koumba, Achille Mayelle and Laschewsky, Andr{\´e} and Schlage, K. and R{\"o}hlsberger, Ralf and Roth, Stephan V. and Cubitt, Robert and M{\"u}ller-Buschbaum, Peter},
  title     = {Swelling and switching kinetics of gold coated end-capped poly(N-isopropylacrylamide) thin films},
  issn      = {0024-9297},
  doi       = {10.1021/Ma902637a},
  year      = {2010},
  abstract  = {Thin thermoresponsive hydrogel films of poly(N-isopropylacrylamide) end-capped with n-butyltrithiocarbonate(nbc- PNIPAM) oil si I icon supports with a gold layer on top, causing an asymmetric confinement, are investigated. For two different gold layer thicknesses (nominally 0.4 and 5 rim), the swelling and switching kinetics are probed with in situ neutron reflectivity. With a temperature jump from 23 to 40 degrees C the film is switched from a swollen into a collapsed state. For the thin gold layer this switching is faster as compared to the thick gold layer. The switching is a two-step process of water release and a subsequent structural relaxation. fit swelling and deswelling cycles, aging of the films is probed. After five cycles, the film exhibits enhanced water storage capacity. Grazing-incidence small-angle X-ray scattering (GISAXS) shows that these gold coated nbc-PNIPAM films do not age with respect to the inner structure but slightly roughen at the gold surface. As revealed by atomic force microscopy, the morphology of the gold layer is changed by the water uptake and release.},
  language  = {en}
}
@article{HarmsRaetzkeFaupeletal.2010,
  author    = {Harms, Stephan and Raetzke, Klaus and Faupel, Franz and Egger, Werner and Ravello, Lori Boyd de and Laschewsky, Andr{\´e} and Wang, Weinan and M{\"u}ller-Buschbaum, Peter},
  title     = {Free volume and swelling in thin films of poly(n-isopropylacrylamide) end-capped with n-butyltrithiocarbonate},
  issn      = {1022-1336},
  doi       = {10.1002/marc.201000067},
  year      = {2010},
  abstract  = {The free volume in thin films of poly(N-isopropylacrylamid) end-capped with n-butyltrio-carbonate (nbc-PNIPAM) is probed with positron annihilation lifetime spectroscopy (PALS). The PALS measurements are performed as function of energy to obtain depth profiles of the free volume of nbc-PNIPAM films. The range of nbc-PNIPAM films with thicknesses from 40 to 200 nm is focused. With decreasing film thickness the free volume increases in good agreement with an increase in the maximum swelling capability of the nbc-PNIPAM films. Thus in thin hydrogel films the sorption and swelling behavior is governed by free volume.},
  language  = {en}
}
@article{SumpfMaiwaldMulleretal.2012,
  author    = {Sumpf, Bernd and Maiwald, Martin and Muller, Andre and Ginolas, Arnim and Haeusler, Karl and Erbert, Goetz and Traenkle, Guenther},
  title     = {Reliable operation for 14 500 h of a wavelength-stabilized Diode Laser System on a Microoptical Bench at 671 nm},
  series = {IEEE transactions on components, packaging and manufacturing technology},
  volume    = {2},
  journal   = {IEEE transactions on components, packaging and manufacturing technology},
  number    = {1},
  publisher = {Inst. of Electr. and Electronics Engineers},
  address   = {Piscataway},
  issn      = {2156-3950},
  doi       = {10.1109/TCPMT.2011.2171342},
  pages     = {116 -- 121},
  year      = {2012},
  abstract  = {Reliability tests for wavelength-stabilized compact diode laser systems emitting at 671 nm are presented. The devices were mounted on microoptical benches with the dimensions of 13 mm x 4 mm. Reflecting Bragg gratings were used for wavelength stabilization and emission width narrowing. The reliability tests were performed at 25 degrees C and at an output power up to 10 mW per micrometer stripe width of the gain medium. Reliable operation could be demonstrated over a test time up to 14 500 h at an output power up to 1.0 W. Environmental tests using random vibrations with acceleration up to 29 g were performed without deterioration of the devices.},
  language  = {en}
}
@article{KreuzerLindenmeirGeigeretal.2021,
  author    = {Kreuzer, Lucas and Lindenmeir, Christoph and Geiger, Christina and Widmann, Tobias and Hildebrand, Viet and Laschewsky, Andr{\´e} and Papadakis, Christine M. and M{\"u}ller-Buschbaum, Peter},
  title     = {Poly(sulfobetaine) versus poly(N-isopropylmethacrylamide)},
  series = {Macromolecules : a publication of the American Chemical Society},
  volume    = {54},
  journal   = {Macromolecules : a publication of the American Chemical Society},
  number    = {3},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0024-9297},
  doi       = {10.1021/acs.macromol.0c02281},
  pages     = {1548 -- 1556},
  year      = {2021},
  abstract  = {The swelling and co-nonsolvency behaviors in pure H2O and in a mixed H2O/CH3OH vapor atmosphere of two different polar, water-soluble polymers in thin film geometry are studied in situ. Films of a zwitterionic poly(sulfobetaine), namely, poly[3-((2-(methacryloyloxy)ethyl)dimethylammonio) propane-1-sulfonate] (PSPE), and a polar nonionic polymer, namely, poly(N-isopropylmethacrylamide) (PNIPMAM), are investigated in real time by spectral reflectance (SR) measurements and Fourier transform infrared (FTIR) spectroscopy. Whereas PSPE is insoluble in methanol, PNIPMAM is soluble but exhibits cononsolvency behavior in water/methanol mixtures. First, the swelling of PSPE and PNIPMAM thin films in H2O vapor is followed. Subsequently, CH3OH is added to the vapor atmosphere, and its contracting effect on the water-swollen films is monitored, revealing a co-nonsolvency-type behavior for PNIPMAM and PSPE. SR measurements indicate that PSPE and PNIPMAM behave significantly different during the H2O swelling and subsequent exposure to CH3OH, not only with respect to the amounts of absorbed water and CH3OH, but also to the cosolvent-induced contraction mechanisms. While PSPE thin films exhibit an abrupt one-step contraction, the contraction of PNIPMAM thin films occurs in two steps. FTIR studies corroborate these findings on a molecular scale and reveal the role of the specific functional groups, both during the swelling and the cosolvent-induced switching of the solvation state.},
  language  = {en}
}
@article{KreuzerWidmannGeigeretal.2021,
  author    = {Kreuzer, Lucas and Widmann, Tobias and Geiger, Christina and Wang, Peixi and Vagias, Apostolos N. and Heger, Julian Eliah and Haese, Martin and Hildebrand, Viet and Laschewsky, Andr{\´e} and Papadakis, Christine M. and M{\"u}ller-Buschbaum, Peter},
  title     = {Salt-dependent phase transition behavior of doubly thermoresponsive poly(sulfobetaine)-based diblock copolymer thin films},
  series = {Langmuir : the ACS journal of surfaces and colloids / American Chemical Society},
  volume    = {37},
  journal   = {Langmuir : the ACS journal of surfaces and colloids / American Chemical Society},
  number    = {30},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0743-7463},
  doi       = {10.1021/acs.langmuir.1c01342},
  pages     = {9179 -- 9191},
  year      = {2021},
  abstract  = {The water vapor-induced swelling, as well as subsequent phase-transition kinetics, of thin films of a diblock copolymer (DBC) loaded with different amounts of the salt NaBr, is investigated in situ. In dilute aqueous solution, the DBC features an orthogonally thermoresponsive behavior. It consists of a zwitterionic poly(sulfobetaine) block, namely, poly(4-(N-(3'-methacrylamidopropyl)-N, N-dimethylammonio) butane-1-sulfonate) (PSBP), showing an upper critical solution temperature, and a nonionic block, namely, poly(N-isopropylmethacrylamide) (PNIPMAM), exhibiting a lower critical solution temperature. The swelling kinetics in D2O vapor at 15 degrees C and the phase transition kinetics upon heating the swollen film to 60 degrees C and cooling back to 15 degrees C are followed with simultaneous time-of-flight neutron reflectometry and spectral reflectance measurements. These are complemented by Fourier transform infrared spectroscopy. The collapse temperature of PNIPMAM and the swelling temperature of PSBP are found at lower temperatures than in aqueous solution, which is attributed to the high polymer concentration in the thin-film geometry. Upon inclusion of sub-stoichiometric amounts (relative to the monomer units) of NaBr in the films, the water incorporation is significantly increased. This increase is mainly attributed to a salting-in effect on the zwitterionic PSBP block. Whereas the addition of NaBr notably shifts the swelling temperature of PSBP to lower temperatures, the collapse temperature of PNIPMAM remains unaffected by the presence of salt in the films.},
  language  = {en}
}
@article{WangGeigerKreuzeretal.2022,
  author    = {Wang, Peixi and Geiger, Christina and Kreuzer, Lucas and Widmann, Tobias and Reitenbach, Julija and Liang, Suzhe and Cubitt, Robert and Henschel, Cristiane and Laschewsky, Andr{\´e} and Papadakis, Christine M. and M{\"u}ller-Buschbaum, Peter},
  title     = {Poly(sulfobetaine)-based diblock copolymer thin films in water/acetone atmosphere: modulation of water hydration and co-nonsolvency-triggered film contraction},
  series = {Langmuir : the ACS journal of surfaces and colloids},
  volume    = {38},
  journal   = {Langmuir : the ACS journal of surfaces and colloids},
  number    = {22},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0743-7463},
  doi       = {10.1021/acs.langmuir.2c00451},
  pages     = {6934 -- 6948},
  year      = {2022},
  abstract  = {The water swelling and subsequent solvent exchange including co-nonsolvency behavior of thin films of a doubly thermo-responsive diblock copolymer (DBC) are studied viaspectral reflectance, time-of-flight neutron reflectometry, and Fourier transform infrared spectroscopy. The DBC consists of a thermo-responsive zwitterionic (poly(4-((3-methacrylamidopropyl) dimethylammonio) butane-1-sulfonate)) (PSBP) block, featuring an upper critical solution temperature transition in aqueous media but being insoluble in acetone, and a nonionic poly(N-isopropylmethacrylamide) (PNIPMAM) block, featuring a lower critical solution temperature transition in water, while being soluble in acetone. Homogeneous DBC films of 50-100 nm thickness are first swollen in saturated water vapor (H2OorD2O), before they are subjected to a contraction process by exposure to mixed saturated water/acetone vapor (H2OorD2O/acetone-d6 = 9:1 v/v). The affinity of the DBC film toward H2O is stronger than for D2O, as inferred from the higher film thickness in the swollen state and the higher absorbed water content, thus revealing a pronounced isotope sensitivity. During the co-solvent-induced switching by mixed water/acetone vapor, a two-step film contraction is observed, which is attributed to the delayed expulsion of water molecules and uptake of acetone molecules. The swelling kinetics are compared for both mixed vapors (H2O/acetone-d6 and D2O/acetone-d6) and with those of the related homopolymer films. Moreover, the concomitant variations of the local environment around the hydrophilic groups located in the PSBP and PNIPMAM blocks are followed. The first contraction step turns out to be dominated by the behavior of the PSBP block, where as the second one is dominated by the PNIPMAM block. The unusual swelling and contraction behavior of the latter block is attributed to its co-nonsolvency behavior. Furthermore, we observe cooperative hydration effects in the DBC films, that is, both polymer blocks influence each other's solvation behavior.},
  language  = {en}
}
@article{AdelsbergerGrilloKulkarnietal.2013,
  author    = {Adelsberger, Joseph and Grillo, Isabelle and Kulkarni, Amit and Sharp, Melissa and Bivigou Koumba, Achille Mayelle and Laschewsky, Andr{\´e} and M{\"u}ller-Buschbaum, Peter and Papadakis, Christine M.},
  title     = {Kinetics of aggregation in micellar solutions of thermoresponsive triblock copolymers - influence of concentration, start and target temperatures},
  series = {Soft matter},
  volume    = {9},
  journal   = {Soft matter},
  number    = {5},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1744-683X},
  doi       = {10.1039/c2sm27152d},
  pages     = {1685 -- 1699},
  year      = {2013},
  abstract  = {In aqueous solution, symmetric triblock copolymers with a thermoresponsive middle block and hydrophobic end blocks form flower-like core-shell micelles which collapse and aggregate upon heating through the cloud point (CP). The collapse of the micellar shell and the intermicellar aggregation are followed in situ and in real-time using time-resolved small-angle neutron scattering (SANS), while heating micellar solutions of a poly((styrene-d(8))-b-(N-isopropyl acrylamide)-b-(styrene-d(8))) triblock copolymer in D2O rapidly through their CP. The influence of polymer concentration as well as of the start and target temperatures is addressed. In all cases, the micellar collapse is very fast. The collapsed micelles immediately form small clusters which contain voids. They densify which slows down or even stops their growth. For low concentrations and target temperatures just above the CP, i.e. shallow temperature jumps, the subsequent growth of the clusters is described by diffusion-limited aggregation. In contrast, for higher concentrations and/or higher target temperatures, i.e. deep temperature jumps, intermicellar bridges dominate the growth. Eventually, in all cases, the clusters coagulate which results in macroscopic phase separation. For shallow temperature jumps, the cluster surfaces stay rough; whereas for deep temperature jumps, a concentration gradient develops at late stages. These results are important for the development of conditions for thermal switching in applications, e.g. for the use of thermoresponsive micellar systems for transport and delivery purposes.},
  language  = {en}
}
@article{MiasnikovaLaschewskyDePaolietal.2012,
  author    = {Miasnikova, Anna and Laschewsky, Andr{\´e} and De Paoli, Gabriele and Papadakis, Christine M. and M{\"u}ller-Buschbaum, Peter and Funari, Sergio S.},
  title     = {Thermoresponsive Hydrogels from Symmetrical Triblock Copolymers Poly(styrene-block-(methoxy diethylene glycol acrylate)-block-styrene)},
  series = {Langmuir},
  volume    = {28},
  journal   = {Langmuir},
  number    = {9},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0743-7463},
  doi       = {10.1021/la204665q},
  pages     = {4479 -- 4490},
  year      = {2012},
  abstract  = {A series of symmetrical, thermo-responsive triblock copolymers was prepared by reversible addition fragmentation chain transfer (RAFT) polymerization, and studied in aqueous solution with respect to their ability to form hydrogels. Triblock copolymers were composed of two identical, permanently hydrophobic outer blocks, made of low molar mass polystyrene, and of a hydrophilic inner block of variable length, consisting of poly(methoxy diethylene glycol acrylate) PMDEGA. The polymers exhibited a LCST-type phase transition in the range of 20-40 degrees C, which markedly depended on molar mass and concentration. Accordingly, the triblock copolymers behaved as amphiphiles at low temperatures, but became water-insoluble at high temperatures. The temperature dependent self-assembly of the amphiphilic block copolymers in aqueous solution was studied by turbidimetry and rheology at concentrations up to 30 wt \%, to elucidate the impact of the inner thermoresponsive block on the gel properties. Additionally, small-angle X-ray scattering (SAXS) was performed to access the structural changes in the gel with temperature. For all polymers a gel phase was obtained at low temperatures, which underwent a gel-sol transition at intermediate temperatures, well below the cloud point where phase separation occurred. With increasing length of the PMDEGA inner block, the gel-sol transition shifts to markedly lower concentrations, as well as to higher transition temperatures. For the longest PMDEGA block studied (DPn about 450), gels had already formed at 3.5 wt \% at low temperatures. The gel-sol transition of the hydrogels and the LCST-type phase transition of the hydrophilic inner block were found to be independent of each other.},
  language  = {en}
}
@article{ZhongAdelsbergerNiedermeieretal.2013,
  author    = {Zhong, Qi and Adelsberger, Joseph and Niedermeier, M. A. and Golosova, Anastasi and Bivigou Koumba, Achille Mayelle and Laschewsky, Andr{\´e} and Funari, S. S. and Papadakis, Christine M. and M{\"u}ller-Buschbaum, Peter},
  title     = {The influence of selective solvents on the transition behavior of poly(styrene-b-monomethoxydiethylenglycol-acrylate-b-styrene) thick films},
  series = {Colloid and polymer science : official journal of the Kolloid-Gesellschaft},
  volume    = {291},
  journal   = {Colloid and polymer science : official journal of the Kolloid-Gesellschaft},
  number    = {6},
  publisher = {Springer},
  address   = {New York},
  issn      = {0303-402X},
  doi       = {10.1007/s00396-012-2879-4},
  pages     = {1439 -- 1451},
  year      = {2013},
  abstract  = {Thick poly(styrene-b-monomethoxydiethylenglycol-acrylate-b-styrene) [P(S-b-MDEGA-b-S)] films (thickness 5 mu m) are prepared from different solvents on flexible substrates by solution casting and investigated with small-angle X-ray scattering. As the solvents are either PS- or PMDEGA-selective, micelles with different core-shell micellar structures are formed. In PMDEGA-selective solvents, the PS block is the core and PMDEGA is the shell, whereas in PS-selective solvents, the order is reversed. After exposing the films to liquid D2O, the micellar structure inside the films prepared from PMDEGA-selective solvents remains unchanged and only the PMDEGA (shell part) swells. On the contrary, in the films prepared from PS-selective solvents, the micelles revert the core and the shell. This reversal causes more entanglements of the PMDEGA chains between the micelles. Moreover, the thermal collapse transition of the PMDEGA block in liquid D2O is significantly broadened. Irrespective of the solvent used for film preparation, the swollen PMDEGA shell does not show a prominent shrinkage when passing the phase transition, and the transition process occurs via compaction. The collapsed micelles have a tendency to densely pack above the transition temperature.},
  language  = {en}
}