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Workshops, Kongresse und Seminare des Helmholtz-Zentrums Dresden-Rossendorf (HZDR)

Hier finden Sie Informationen zu Terminen und Programmen für Workshops, Kongresse oder Seminare, die vom HZDR veranstaltet oder (mit)organisiert werden.

Auf den folgenden Institutsseiten finden Sie weitere Informationen zu geplanten Veranstaltungen.


Ausblick

26.01.2022 13:00 - 14:00 Uhr Zentrumskolloquium

Maram Naes (TU Berlin) "Probing Chemical and Micromorphological Properties of Gold in Historical Wall Paintings Using Lab and Synchrotron Investigation Methods"

Gilding materials and technology of Nabataean gilded wall paintings dating back to the 1st century AD were identified using various spectroscopic techniques. Micro-spectroscopic analytical investigations were performed on wall painting and stucco fragments from various painted facades in Petra. Non-invasive (NI) and non-destructive (ND) analytical methods were prioritised in our investigation approach. Beside Optical Light Microscopy (OM) and Environmental Scanning Electron Microscopy (ESEM), 2D and 3D Micro X-Ray Fluorescence (µXRF) with laboratory and synchrotron sources were utilized. 2D elemental mapping of major components allowed the detection of visually invisible (to bare eye) nanogold clusters. Moreover, laboratory and synchrotron Fourier Transform Infrared Spectroscopy (FTIR) were used to investigate the molecular composition of the gilded samples. Chemical speciation of gold and iron in the historical samples were also studied using NI and ND X-Ray Absorption Spectroscopy, both Near Edge (XANES) and Extended (EXAFS).

The results allowed defining gilding technology in Nabataean gilded wall paintings and stucco and categorising the paintings accordingly. Results showed that gilding materials and techniques did influence the current condition of gold layer at both macro and micro scales. A micrographic glossary of gold’s layer micromorphology was developed and correlated with various deterioration mechanisms.

Remarkably, gold and iron speciation in the historical samples is found to be influenced by both composition and condition of the gilded painted surfaces. EXAFS analysis at Au-L3 edge (11.919 eV) allowed the detection of various gold species indicating possible reactions with iron oxide paint layer as well as inherent and surrounding soluble chloride salts. Iron speciation showed the presence of various iron oxides and sulfates in relation to composition and condition. Thermal influence (uncontrolled fire event in site’s history) on its oxidation state was evident in the pre-edge region at 7.1135 keV. These findings are reported for the first time in historical gilded paintings, certainly Nabataean. A selection of our results will be presented in this webinar.


Rückblick

14.12.2021

Cross-Innovation Challenge: Abwasser meets Energiegewinnung, Recycling und moderne Sensorik

Online-Veranstaltung

Die Veranstaltung wurde vom HZDR gemeinsam mit dem Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) organisiert.


7.-10.12.2021

TEACH - Talk about Education Accross Communities in Helmholtz

Online-Veranstaltung


6.-9.12.2021

3. CASUS-Jahrestagung: "Digitale Zwillinge komplexer Systeme"

Online-Veranstaltung


6.12.2021

ML@HZDR Symposium 2021

Online-Veranstaltung


27.09.2021

Zentrumskolloquium
Prof. Dr. Getrud Zwicknagl (TU Braunschweig) "Our present understanding of superconductivity"


09.06.2021

Zentrumskolloquium
Prof. Dr. Katja Matthes (GEOMAR) "Die Rolle des Ozeans im Klimawandel: Chancen und Risiken"


13.01.2021

Zentrumskolloquium
Prof. Dr. Achim Stahl (RWTH Aachen) „The Einstein Telescope – the next generation of gravitational wave detectors”