The German chemist-apothecary Caspar Georg Carl Reinwardt (1773-1854) offers a fascinating window on Dutch culture and society in the late eighteenth and early nineteenth centuries. By providing an... Show moreThe German chemist-apothecary Caspar Georg Carl Reinwardt (1773-1854) offers a fascinating window on Dutch culture and society in the late eighteenth and early nineteenth centuries. By providing an in-depth analysis of his multi-faceted career in the Netherlands and the Malay Archipelago, this study sheds light on the co-evolutionary character of science, governance, and empire. It argues that seeds of Reinwardt’s professional flexibility lay in his practical training in one of Amsterdam’s chemical workshops and his socialization in a broader cultural context where the improvement of society and economy played a crucial role. Show less
Common alkyd paint will not have dried within two hours without drying catalysts. The drying catalyst (also called __drier__) that is generally used is based on the heavy metal cobalt. Since cobalt... Show moreCommon alkyd paint will not have dried within two hours without drying catalysts. The drying catalyst (also called __drier__) that is generally used is based on the heavy metal cobalt. Since cobalt salts are suspected to be carcinogenic, it is of the utmost importance that alternative driers are found and that cobalt can be replaced as a drier in alkyd paint. In this thesis newly developed manganese compounds are presented which show a comparable or better drying activity than existing cobalt driers. These manganese driers are thus potential replacements for the toxic cobalt compounds. Results pertaining to the mechanism of action of the new manganese driers are also discussed. These results will make the future development of alkyd paint driers easier. Huis-tuin-en-keuken alkydverf is uit zichzelf niet binnen twee uur droog. Daarom worden drogingsversnellers (katalysatoren) aan de verf toegevoegd, om het drogingsproces te versnellen. De meest gebruikte drogingskatalysator (ook wel __droger__ genoemd) in alkydverf is gebaseerd op het zware metaal kobalt. Aangezien kobalt vermeend carcinogeen is, is het noodzaak om alternatieve drogers te vinden zodat kobalt vervangen kan worden. In dit proefschrift worden (nieuw ontwikkelde) mangaanverbindingen gepresenteerd die dezelfde of soms zelfs een betere drogingsactiviteit vertonen als de bestaande kobaltdroger en dus als mogelijke vervanger aangemerkt kunnen worden. Ook worden resultaten gepresenteerd mbt de precieze werking van de mangaandrogers, zodat het in de toekomst makkelijker zal zijn nieuwe drogers te ontwikkelen voor bijvoorbeeld een specifieke verfformulering. Show less