Achieving low cost, safe, reproducible and high performance superconducting thin films of YBa2Cu3O7-δ is essential to bring this material to the energy market. Here, we report on the chemical solution deposition of YBa2Cu3O7-δ nanocomposites from environmentally benign precursors with a low-fluorine content. Preformed ZrO2 nanocrystals (3.5 nm) were stabilized in a methanolic precursor solution via two strategies: charge stabilization and steric stabilization. Counter-intuitively, charge stabilization did not result in high quality superconducting layers, while the steric stabilization resulted in highly reproducible nanocomposite thin films with a self-field Jc of 4-5 MA cm -² (77 K) and a much smaller decay of Jc with magnetic field compared to YBa2Cu3O7-δ without nanocrystals. In addition, these nanocomposite films show a strong pinning force enhancement and a reduced Jc anisotropy compared to undoped YBa2Cu3O7-δ films. Given the relationship between the nanocrystal surface chemistry and final nanocomposite performance, we expect these results to be also relevant for other nanocomposite research.-2 -

Di‐, tri‐, and tetrathienyl‐substituted polycyclic aromatic fluorophores were prepared from different aryldi‐, aryltri‐, or aryltetrahalides by a simple and fast Suzuki coupling. The reaction was optimized for the synthesis of the desired materials on multigram scale. The coupled products were converted into the corresponding iodides through iodination with N‐iodosuccinimide. The iodides turned out to be versatile starting materials for applications, such as periodic mesoporous organosilica syntheses. They were converted into a variety of new trimethoxysilyl arenes by using a very efficient Pd‐mediated C–Si cross‐coupling, which was also extended to the corresponding thienyl bromides by using a dimeric PdI catalyst. All compounds were characterized by 1H NMR, 13C NMR, 29Si NMR, and ATR‐IR spectroscopy and HRMS.

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The present study focused on genotoxic properties of the carcinogenic phenylpropanoids α-asarone and β-asarone, which are found in several herbs and spices, such as Acorus calamus or Acorus gramineus. Cytotoxic and genotoxic effects were determined in human liver carinoma HepG2 cells, in hamster lung fibroblast V79 cells and in human cytochrome P450 1A2 and human sulfotransferase 1C2 transfected V79 cells (tV79). The Alamar blue assay was used to measure cytotoxicity of both isomers prior to the identification of DNA damaging properties by single cell gel electrophoresis (comet assay). Furthermore, the phosphorylation status of the histone H2AX, as a response of DNA double strand breaks, was investigated in HepG2 cells by Western blot analysis and visualized by immunofluorescence microscopy. After 24 h of incubation a significant reduction of cell viability was found. Moreover, both asarone isomers induced DNA strand breaks in V79 cells after 1 h of incubation. In tV79 cells even more pronounced DNA damaging properties were exhibited, whereas in HepG2 cells the compounds were found to be less effective. Furthermore, in tV79 cells a significant increase of formamidopyrimidine-DNA-glycosylase-sensitive sites was observed. DNA strand breaks, induced by aA, were to some extent characterized as DNA double strand breaks. In summary, asarone-induced cytotoxicity and genotoxicity is strongly influenced by the cellular metabolic enzyme status and therefore, a contribution of their respective metabolites to in vitro toxicity can be suggested.