@misc{BanerjeeStuekerSaalfrank2015,
  author    = {Banerjee, Shiladitya and St{\"u}ker, Tony and Saalfrank, Peter},
  title     = {Vibrationally resolved optical spectra of modified diamondoids obtained from time-dependent correlation function methods},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-86826},
  year      = {2015},
  abstract  = {Optical properties of modified diamondoids have been studied theoretically using vibrationally resolved electronic absorption, emission and resonance Raman spectra. A time-dependent correlation function approach has been used for electronic two-state models, comprising a ground state (g) and a bright, excited state (e), the latter determined from linear-response, time-dependent density functional theory (TD-DFT). The harmonic and Condon approximations were adopted. In most cases origin shifts, frequency alteration and Duschinsky rotation in excited states were considered. For other cases where no excited state geometry optimization and normal mode analysis were possible or desired, a short-time approximation was used. The optical properties and spectra have been computed for (i) a set of recently synthesized sp2/sp3 hybrid species with C[double bond, length as m-dash]C double-bond connected saturated diamondoid subunits, (ii) functionalized (mostly by thiol or thione groups) diamondoids and (iii) urotropine and other C-substituted diamondoids. The ultimate goal is to tailor optical and electronic features of diamondoids by electronic blending, functionalization and substitution, based on a molecular-level understanding of the ongoing photophysics.},
  language  = {en}
}
@misc{MondalMarquardtJaniaketal.2015,
  author    = {Mondal, Suvendu Sekhar and Marquardt, Dorothea and Janiak, Christoph and Holdt, Hans-J{\"u}rgen},
  title     = {Use of a 4,5-dicyanoimidazolate anion based ionic liquid for the synthesis of iron and silver nanoparticles},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-89696},
  pages     = {5476 -- 5483},
  year      = {2015},
  abstract  = {Sixteen new ionic liquids (ILs) with tetraethylammonium, 1-butyl-3-methylimidazolium, 3-methyl-1-octylimidazolium and tetrabutylphosphonium cations paired with 2-substituted 4,5-dicyanoimidazolate anions (substituent at C2 = methyl, trifluoromethyl, pentafluoroethyl, N,N′-dimethyl amino and nitro) have been synthesized and characterized by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA). The effects of cation and anion type and structure of the resulting ILs, including several room temperature ionic liquids (RTILs), are reflected in the crystallization, melting points and thermal decomposition of the ILs. ILs exhibited large liquid and crystallization ranges and formed glasses on cooling with glass transition temperatures in the range of -22 to -71 °C. We selected one of the newly designed ILs due to its bigger size, compared to the common conventional IL anion and high electron-withdrawing nitrile group leads to an overall stabilization anion that may stabilize the metal nanoparticles. Stable and better separated iron and silver nanoparticles are obtained by the decomposition of corresponding Fe2(CO)9 and AgPF6, respectively, under N2-atmosphere in newly designed nitrile functionalized 4,5-dicyanoimidazolate anion based IL. Very small and uniform size for Fe-nanoparticles of about 1.8 ± 0.6 nm were achieved without any additional stabilizers or capping molecules. Comparatively bigger size of Ag-nanoparticles was obtained through the reduction of AgPF6 by hydrogen gas. Additionally, the AgPF6 precursor was decomposed under microwave irradiation (MWI), fabricating nut-in-shell-like, that is, core-separated-from-shell Ag-nano-structures.},
  language  = {en}
}
@misc{KumkeKlier2015,
  author    = {Kumke, Michael Uwe and Klier, Dennis Tobias},
  title     = {Upconversion NaYF4:Yb:Er nanoparticles co-doped with Gd3+ and Nd3+ for thermometry on the nanoscale},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-102677},
  pages     = {67149 -- 67156},
  year      = {2015},
  abstract  = {In the present work, the upconversion luminescence properties of oleic acid capped NaYF4:Gd3+:Yb3+:Er3+ upconversion nanoparticles (UCNP) with pure β crystal phase and Nd3+ ions as an additional sensitizer were studied in the temperature range of 288 K < T < 328 K. The results of this study showed that the complex interplay of different mechanisms and effects, causing the special temperature behavior of the UCNP can be developed into thermometry on the nanoscale, e.g. to be applied in biological systems on a cellular level. The performance was improved by the use of Nd3+ as an additional dopant utilizing the cascade sensitization mechanism in tri-doped UCNP.},
  language  = {en}
}
@misc{KlierKumke2015,
  author    = {Klier, Dennis Tobias and Kumke, Michael Uwe},
  title     = {Upconversion NaYF4:Yb:Er nanoparticles co-doped with Gd3+ and Nd3+ for thermometry on the nanoscale},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-89618},
  pages     = {67149 -- 67156},
  year      = {2015},
  abstract  = {In the present work, the upconversion luminescence properties of oleic acid capped NaYF4:Gd3+:Yb3+:Er3+ upconversion nanoparticles (UCNP) with pure β crystal phase and Nd3+ ions as an additional sensitizer were studied in the temperature range of 288 K < T < 328 K. The results of this study showed that the complex interplay of different mechanisms and effects, causing the special temperature behavior of the UCNP can be developed into thermometry on the nanoscale, e.g. to be applied in biological systems on a cellular level. The performance was improved by the use of Nd3+ as an additional dopant utilizing the cascade sensitization mechanism in tri-doped UCNP.},
  language  = {en}
}
@misc{LohrenBornhorstGallaetal.2015,
  author    = {Lohren, Hanna and Bornhorst, Julia and Galla, Hans-Joachim and Schwerdtle, Tanja},
  title     = {The blood-cerebrospinal fluid barrier},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82089},
  year      = {2015},
  abstract  = {Exposure to organic mercury compounds promotes primarily neurological effects. Although methylmercury is recognized as a potent neurotoxicant, its transfer into the central nervous system (CNS) is not fully evaluated. While methylmercury and thiomersal pass the blood-brain barrier, limited data are available regarding the second brain regulating interface, the blood-cerebrospinal fluid (CSF) barrier. This novel study was designed to investigate the effects of organic as well as inorganic mercury compounds on, and their transfer across, a porcine in vitro model of the blood-CSF barrier for the first time. The barrier system is significantly more sensitive towards organic Hg compounds as compared to inorganic compounds regarding the endpoints cytotoxicity and barrier integrity. Whereas there are low transfer rates from the blood side to the CSF side, our results strongly indicate an active transfer of the organic mercury compounds out of the CSF. These results are the first to demonstrate an efflux of organic mercury compounds regarding the CNS and provide a completely new approach in the understanding of mercury compounds specific transport.},
  language  = {en}
}
@misc{PrestelMoeller2015,
  author    = {Prestel, Andreas and M{\"o}ller, Heiko Michael},
  title     = {Spatio-temporal control of cellular uptake achieved by photoswitchable cell-penetrating peptides},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-89658},
  pages     = {701 -- 704},
  year      = {2015},
  abstract  = {The selective uptake of compounds into specific cells of interest is a major objective in cell biology and drug delivery. By incorporation of a novel, thermostable azobenzene moiety we generated peptides that can be switched optically between an inactive state and an active, cell-penetrating state with excellent spatio-temporal control.},
  language  = {en}
}
@misc{MegowRoehrSchmidtamBuschetal.2015,
  author    = {Megow, J{\"o}rg and R{\"o}hr, Merle I. S. and Schmidt am Busch, Marcel and Renger, Thomas and Mitrić, Roland and Kirstein, Stefan and Rabe, J{\"u}rgen P. and May, Volkhard},
  title     = {Site-dependence of van der Waals interaction explains exciton spectra of double-walled tubular J-aggregates},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-79978},
  pages     = {6741 -- 6747},
  year      = {2015},
  abstract  = {The simulation of the optical properties of supramolecular aggregates requires the development of methods, which are able to treat a large number of coupled chromophores interacting with the environment. Since it is currently not possible to treat large systems by quantum chemistry, the Frenkel exciton model is a valuable alternative. In this work we show how the Frenkel exciton model can be extended in order to explain the excitonic spectra of a specific double-walled tubular dye aggregate explicitly taking into account dispersive energy shifts of ground and excited states due to van der Waals interaction with all surrounding molecules. The experimentally observed splitting is well explained by the site-dependent energy shift of molecules placed at the inner or outer side of the double-walled tube, respectively. Therefore we can conclude that inclusion of the site-dependent dispersive effect in the theoretical description of optical properties of nanoscaled dye aggregates is mandatory.},
  language  = {en}
}
@misc{JahnBuschmannHille2015,
  author    = {Jahn, Karolina and Buschmann, Volker and Hille, Carsten},
  title     = {Simultaneous Fluorescence and Phosphorescence Lifetime Imaging Microscopy in Living Cells},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-82156},
  year      = {2015},
  abstract  = {In living cells, there are always a plethora of processes taking place at the same time. Their precise regulation is the basis of cellular functions, since small failures can lead to severe dysfunctions. For a comprehensive understanding of intracellular homeostasis, simultaneous multiparameter detection is a versatile tool for revealing the spatial and temporal interactions of intracellular parameters. Here, a recently developed time-correlated single-photon counting (TCSPC) board was evaluated for simultaneous fluorescence and phosphorescence lifetime imaging microscopy (FLIM/PLIM). Therefore, the metabolic activity in insect salivary glands was investigated by recording ns-decaying intrinsic cellular fluorescence, mainly related to oxidized flavin adenine dinucleotide (FAD) and the μs-decaying phosphorescence of the oxygen-sensitive ruthenium-complex Kr341. Due to dopamine stimulation, the metabolic activity of salivary glands increased, causing a higher pericellular oxygen consumption and a resulting increase in Kr341 phosphorescence decay time. Furthermore, FAD fluorescence decay time decreased, presumably due to protein binding, thus inducing a quenching of FAD fluorescence decay time. Through application of the metabolic drugs antimycin and FCCP, the recorded signals could be assigned to a mitochondrial origin. The dopamine-induced changes could be observed in sequential FLIM and PLIM recordings, as well as in simultaneous FLIM/PLIM recordings using an intermediate TCSPC timing resolution.},
  language  = {en}
}
@misc{KirchheckerTroegerMuellerBakeetal.2015,
  author    = {Kirchhecker, Sarah and Tr{\"o}ger-M{\"u}ller, Steffen and Bake, Sebastian and Antonietti, Markus and Taubert, Andreas and Esposito, Davido},
  title     = {Renewable pyridinium ionic liquids from the continuous hydrothermal decarboxylation of furfural-amino acid derived pyridinium zwitterions},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-81390},
  year      = {2015},
  abstract  = {Fully renewable pyridinium ionic liquids were synthesised via the hydrothermal decarboxylation of pyridinium zwitterions derived from furfural and amino acids in flow. The functionality of the resulting ionic liquid (IL) can be tuned by choice of different amino acids as well as different natural carboxylic acids as the counterions. A representative member of this new class of ionic liquids was successfully used for the synthesis of ionogels and as a solvent for the Heck coupling.},
  language  = {en}
}
@misc{BodrovaChechkinCherstvyetal.2015,
  author    = {Bodrova, Anna and Chechkin, Aleksei V. and Cherstvy, Andrey G. and Metzler, Ralf},
  title     = {Quantifying non-ergodic dynamics of force-free granular gases},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-85200},
  year      = {2015},
  abstract  = {Brownianmotion is ergodic in the Boltzmann-Khinchin sense that long time averages of physical observables such as the mean squared displacement provide the same information as the corresponding ensemble average, even at out-of-equilibrium conditions. This property is the fundamental prerequisite for single particle tracking and its analysis in simple liquids. We study analytically and by event-driven molecular dynamics simulations the dynamics of force-free cooling granular gases and reveal a violation of ergodicity in this Boltzmann-Khinchin sense as well as distinct ageing of the system. Such granular gases comprise materials such as dilute gases of stones, sand, various types of powders, or large molecules, and their mixtures are ubiquitous in Nature and technology, in particular in Space. We treat—depending on the physical-chemical properties of the inter-particle interaction upon their pair collisions—both a constant and a velocity-dependent (viscoelastic) restitution coefficient e. Moreover we compare the granular gas dynamics with an effective single particle stochastic model based on an underdamped Langevin equation with time dependent diffusivity. We find that both models share the same behaviour of the ensemble mean squared displacement (MSD) and the velocity correlations in the limit of weak dissipation. Qualitatively, the reported non-ergodic behaviour is generic for granular gases with any realistic dependence of e on the impact velocity of particles.},
  language  = {en}
}