Here, we report on the fabrication of light-switchable and light-responsive membranes based on graphene oxide (GO) modified with azobenzene compounds. Azobenzene and -aminoazobenzene were grafted onto graphene oxide layers by covalent attachment/condensation reaction prior to the membranes' assembly. The modification of GO was proven by the UV-vis, IR, Raman and photoelectron spectroscopy.
View Article and Find Full Text PDFMesocrystals are a class of nanostructured material, where a multiple-length-scale structure is a prerequisite of many interesting phenomena. Resolving the mesocrystal structure is quite challenging due to their structuration on different length scales. The combination of small- and wide-angle X-ray scattering (SAXS and WAXS) techniques offers the possibility of non-destructively probing mesocrystalline structures simultaneously, over multiple length scales to reveal their microscopic structure.
View Article and Find Full Text PDFActa Crystallogr B Struct Sci Cryst Eng Mater
June 2022
Using X-ray scattering, we measured detailed maps of the diffuse scattering intensity distribution and a number of phonon dispersion branches for a single crystal of inorganically formed natural calcite and for high-quality mesocrystals of biogenic calcite from a Mediterranean sea urchin spine. A comparison shows that the known differences in the mechanical properties between the `strong' biogenic and `brittle' abiotic material should be attributed to the mesoscopic architecture of the crystal rather than to a modification of the calcite crystal structure. The data are rationalized by comparing them to the results of ab initio model calculations of lattice dynamics.
View Article and Find Full Text PDFX-ray spectroscopy using high-energy-resolution fluorescence detection (HERFD) has critically increased the information content in X-ray spectra. We extend this technique to the tender X-ray range and present a study at the L-edge of molybdenum. We show how information on the oxidation state, phase composition, and local environment in molybdenum-based compounds can be obtained by analyzing the HERFD L X-ray absorption near-edge structure (XANES).
View Article and Find Full Text PDFIntroduction/aims: Severe acute respiratory syndrome coronavirus-2 2019 (SARS-CoV2/COVID-19) is frequently more severe in individuals with pre-existing respiratory and cardiovascular conditions. The impact on patients with neuromuscular disorders is of concern, but remains largely unknown. Late-onset Pompe disease (LOPD) is a lysosomal-storage disorder characterized by progressive skeletal and respiratory muscle degeneration.
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