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PdI2(Me2dazdt)] is obtained from palladium powder via a 100% atom economical Pd(0) leaching reaction using Me2dazdt (N,N'-dimethyl-perhydrodiazepine-2,3-dithione) and iodine. This complex is a versatile starting point for ligand exchange reactions with (di)phosphines, yielding trans-[PdI2(PPh3)2] and [PdI2(dppe)] (dppe = 1,2-bis(diphenylphosphino)ethane). Further reaction with dithiocarbamates provides compounds of the form [Pd(DTC)(L)n]+ (DTC = dithiocarbamate; L = PPh3, n = 2; L = dppe, n = 1), which are highly active catalysts for regioand chemo-selective C-H bond activation reactions. Using DTC ligands with trimethoxysilyterminated tethers, the palladium(II) units can be attached to the surface of core-shell, silicacoated Fe3O4 nanoparticles. Once tethered, these units formed the catalytically-active component of a recyclable, quasi-heterogeneous, Pd(II)-based catalytic system based on recovered palladium, illustrating the proposed circular model strategy. These investigations contribute to key steps in this process, such as efficient, atom-economical recovery, chemoselectivity of ligand substitution reactions, demonstration of catalytic activity and the potential for immobilization of catalytic surface units derived from recovered metal.

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In the framework of the periodic update of the Sardinian River Basin Management and Water Protection Plans (Italian Law 152/2006, transposition of the 2000/60/EC Directive), we investigated the AQUATOX model feasibility as a tool for assessing the relationships between Driving forces, Pressures, States, Impacts and Responses (DPSIR scheme). To do this, we applied the AQUATOX model to forecast the response of a Sardinian (Italy) river quality status to a set of different environmental perturbations, including nutrient load and water flow variations. The final aim of this work is to study a feasible model, based on a DPSIR scheme, for identifying the necessary and sustainable measures to tackle the criticalities resulting from a set of known environmental perturbations on Sardinian rivers.

In the last decades, the scientific community has developed many methods and approaches for the assessment of surface waters quality status and the relative impacts of anthropogenic pressures including, among the others, municipal and industrial wastewater treatment plants, agriculture, animal farming and many other land uses. According to the Water Framework Directive (WFD; 2000/60/EC), each EU Member State has been committed to identifying River Basin Districts, in which, ideally, every water body within European boundaries should have been included. As a contribution to the quality assessment of the Sardinian River Basin District, in the framework of the project “Hydraulic and environmental modelling for the gap analysis and the identification of programmes of measures aimed to satisfy the environmental quality objectives” funded by the Regione Sardegna, we applied a simplified version of the AQUATOX model, developed for investigating its feasibility and validity in case of missing or poor input data and information, on the river Cixerri case study.