Synthesis and Features of Luminescent Bromo- and Iodohectorite Nanoclay Materials

The smectites represent a versatile class of clay minerals with broad usage in industrial applications, e.g., cosmetics, drug delivery, bioimaging, etc. Synthetic hectorite Na-0.7(Mg5.5Li0.3)[Si8O20](OH)(4) is a distinct material from this class due to its low-cost production method that allows to design its structure to match better the applications. In the current work, we have synthesized for the first time ever nanoclay materials based on the hectorite structure but with the hydroxyl groups (OH-) replaced by Br- or I-, yielding bromohectorite (Br-Hec) and iodohectorite (I-Hec). It was aimed that these materials would be used as phosphors. Thus, OH- replacement was done to avoid luminescence quenching by multiphonon de-excitation. The crystal structure is similar to nanocrystalline fluorohectorite, having the d(001) spacing of 14.30 angstrom and 3 nm crystallite size along the 00l direction. The synthetic materials studied here show strong potential to act as host lattices for optically active species, possessing mesoporous structure with high specific surface area (385 and 363 m(2) g(-1) for Br-Hec and I-Hec, respectively) and good thermal stability up to 800 degrees C. Both materials also present strong blue-green emission under UV radiation and short persistent luminescence (ca. 5 s). The luminescence features are attributed to Ti3+/Ti-IV impurities acting as the emitting center in these materials

Hackmanite-The Natural Glow-in-the-Dark Material

"Glow-in-the-dark" materials are known to practically everyone who has ever traveled by airplane or cruise ship, since they are commonly used for self-lit emergency exit signs. The green afterglow, persistent luminescence (PeL), is obtained from divalent europium doped to a synthetic strontium aluminate, but there are also some natural minerals capable of afterglow. One such mineral is hackmanite, the afterglow of which has never been thoroughly investigated, even if its synthetic versions can compete with some of the best commercially available synthetic PeL materials. Here we combine experimental and computational data to show that the white PeL of natural hackmanite is generated and controlled by a very delicate interplay between the natural impurities present. The results obtained shed light on the PeL phenomenon itself thus giving insight into improving the performance of synthetic materials

A new research agenda for managing socio-cultural integration

Post-acquisition socio-cultural integration has received increasing attention from both scholars and practitioners since the early 1990s. During the past decade, research has increasingly focused on emotions and identity in mergers and acquisitions. This chapter introduces the reader to the vibrant research field and its relevance. This section sets the scene for the book, which provides a deeper understanding of how emotions—both positive and negative—as well as values and identity enable a deeper socio-cultural integration after a merger or acquisition, and how leadership plays a crucial role in making it all happen. This chapter also highlights how the Nordic approach to post-acquisition socio-cultural integration refers to a large community of Nordic academics focusing on the softer social and human side of acquisition, often relying on a huge variety of qualitative methods, and to Nordic companies that are not afraid of adopting a more collaborative approach to post-acquisition integration