Metric survey and possible representations of Historic Architectural Heritage: the case of the Santa Giustina Abbey

The semi-automatic metric survey techniques developed in the past years allow the recording of 3D models with an ever-increasing level of details and accuracies. The 3D database, usually georeferenced in a cartographic system, opens the floor to different kind of representations (e.g. 2D drawings, 3D models, digital animations, AR/MR applications etc.) conceived to satisfy different requirements at different graphic scales and aimed to increasing the knowledge of Cultural Heritage. The paper introduces some different representations that can be extracted from a 3D database: the “as built” representations, which put in evidence all the irregularities of a real building, as it today appears because of anthropic interventions and endogenous/exogenous events happened during its life. Starting from this 3D database the main task of the representations is interpreting and synthesizing the collected information aiming to recognize the architectural values of the building, the geometric matrices of the shape, the modularity of the composition, and the relationships between architecture and decoration. The Romanesque abbey of Santa Giustina in Sezzadio (Italy), a well preserved building, which considerable dimensions, constructive accuracy, and rich decorations testifying its territorial importance, is a significant case study for these purposes. It is a less documented architecture where metric survey and representations has been produced as a first step to support future researches

Cr(III) Complexes Bearing a β-Ketoimine Ligand for Olefin Polymerization: Are There Differences between Coordinative and Covalent Bonding?

β-ketoimines are extensively applied for the synthesis of organometallic complexes intended as (pre)catalysts for a variety of chemical transformations. We were interested in the synthesis of two Cr complexes bearing a simple bidentate β-ketoimine (L), with different ligand binding modes, as well as their application as a precatalyst in the polymerization of olefins. Complex 1 (L2CrCl3) was obtained by direct reaction of L with CrCl3(THF)3, while, for the synthesis of complex 2 (LCrCl2), the ligand was first deprotonated with nBuLi, giving the β-ketoiminato ligand L─Li+, and then reacted with CrCl3(THF)3. Characterization of the complexes proved that the Cr(III) ion is coordinatively bonded to L in 1, while it is covalently bonded to L in 2. The complexes were then used as precatalysts for the polymerization of ethylene and various cyclic olefins. Upon activation with methylaluminoxane, both the complexes exhibited poor activity in the polymerization of ethylene, whilst they exhibit good productivity in the polymerization of cyclic olefins, affording semicrystalline oligomers, without a significant difference between 1 and 2. To gain more insight, we investigated the reaction of the complexes with the Al-cocatalyst by IR and UV-Vis spectroscopies. The results proved that, in case of 1, the Al-activator deprotonates the ligand, bringing to the formation of an active species analogous to that of 2

An Integrated Characterization Strategy on Board for Recycling of poly(vinyl butyral) (PVB) from Laminated Glass Wastes

: Polyvinyl butyral (PVB) is widely used as an interlayer material in laminated glass applications, mainly in the automotive industry, but also for construction and photovoltaic applications. Post-consumed laminated glass is a waste that is mainly landfilled; nevertheless, it can be revalorized upon efficient separation and removal of adhered glass. PVB interlayers in laminated glass are always plasticized with a significant fraction in the 20-40% w/w range of plasticizer, and they are protected from the environment by two sheets of glass. In this work, the aim is to develop a thorough characterization strategy for PVB films. Neat reference PVB grades intended for interlayer use are compared with properly processed (delaminated) post-consumed PVB grades from the automotive and construction sectors. Methods are developed to open opportunities for recycling and reuse of the latter. The plasticizer content and chemical nature are determined by applying well-known analytical techniques, namely, FT-IR, TGA, NMR. The issue of potential aging during the life cycle of the original laminated material is also addressed through NMR. Based on the findings, a sensor capable of directly sorting PVB post-consumer materials will be developed and calibrated at a later stage