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The structure of five rare filigree spheres from a seventeenth century shipwreck was examined in order to unravel their condition, manufacturing process and function. This study focuses on the application of non-invasive imaging techniques: optical microscopy, X-radiography, X-ray micro-computed tomography and neutron computed tomography. A valuation of different aspects of the applied techniques was made, aiding stakeholders in decision-making on research and conservation. The combination of theory and scientific information was used to obtain an improved understanding of the manufacturing process and function of the filigree spheres., Geo-engineering, RST/Neutron and Positron Methods in Materials

The use of scanning gradients can significantly reduce method-development time in reversed-phase liquid chromatography. However, there is no consensus on how they can best be used. In the present work we set out to systematically investigate various factors and to formulate guidelines., Journal of Chromatography A 1636 (2021) 461780 Contents lists available at ScienceDirect Journal of Chromatography A journal homepage: www.elsevier.com/locate/chroma Measuring and using scanning-gradient data for use in method optimization for liquid chromatography Mimi J. den Uijl a , b , ∗, Peter J. Schoenmakers a , b , Grace K. Schulte c , Dwight R. Stoll c , Maarten R. van Bommel a , b , d , Bob W.J. Pirok a , b , c a University of Amsterdam, van ’t HoffInstitute for Molecular Sciences, Analytical-Chemistry Group, Science Park 904, 1098 XH Amsterdam, the Netherlands b Centre for Analytical Sciences Amsterdam (CASA), The Netherlands c Department of Chemistry, Gustavus Adolphus College, Saint Peter, Minnesota 56082, USA d University of Amsterdam, Amsterdam School for Heritage, Memory and Material Culture, Conservation and Restoration of Cultural Heritage, Johannes Vermeerplein 1, 1071 DV Amsterdam, the Netherlands a r t i c l e i n f o Article history: Received 20 July 2020 Revised 23 November 2020 Accepted 29 November 2020 Available online 2 December 2020 Keywords: Retention prediction Scouting techniques Method optimization, Retention modelling Method development Gradient elution a b s t r a c t The use of scanning gradients can significantly reduce method-development time in reversed-phase liquid chromatography. However, there is no consensus on how they can best be used. In the present work we set out to systematically investigate various factors and to formulate guidelines. Scanning gradients are used to establish retention models for individual analytes. Different retention models were compared by computing the Akaike information criterion and the prediction accuracy. The measurement uncertainty was found to influence the optimum choice of model. The use of a third parameter to account for non- linear relationships was consistently found not to be statistically significant. The duration (slope) of the scanning gradients was not found to influence the accurac