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In recent decades, worldwide wine-growing regions have been affected by increasingly more frequent effects of climate change, such as long period of droughts during the growing season, summer heat waves, and late spring frost events, thus causing concern for the grape quality and production. In this context, it is necessary to develop innovative agronomic practices to counter the various negative effects from those extreme weather events, by equipping the vineyards with effective and reliable multifunctional systems, which are also economically sustainable. Particularly, a multifunctional irrigation system can be used to reduce the risk of extreme weather events and, at the same time, to improve quality and quantity of grape production, reducing their inter-annual variability as well, by providing an optimized plant water nutrition. In a vineyard situated south of Lake Garda (Northern Italy), a multifunctional irrigation system equipped with drippers and mini-sprinklers (the latter to protect from both late spring frost and summer high-temperature event) was assessed. The results obtained for the growing season 2020–21 showed that the optimized drip irrigation reduced water consumption without affecting the grape yield, both in quantity and quality. The frost protection operated by mini-sprinklers increased the air temperature at bud's level of about 1 °C, suggesting a positive effect on plant production. Finally, in 2020, must quality was positively affected by summer sprinkler irrigation, increasing the levels of malic acid and titratable acidity of over 0.7 g L−1 while lowered total soluble solids. Further activities in the 2022 season intend to better assess the water use efficiency of this promising multifunctional system. [ABSTRACT FROM AUTHOR]

New amphiphilic and spin-labile MnIIIcomplexes based on dianionic N4O2-hexadentate sal2trien or sal2bapen ligands, which contain OC6H13, OC12H25, or OC18H37alkoxy substituents at different positions of the salicylidene unit were prepared (H2sal2trien = N,N′′′-bis(salicylidene)-1,4,7,10-tetraazadecane, H2sal2bapen = N,N′′′-bis(salicylidene)-1,5,8,12-tetraazadodecane). According to electrochemical measurements, these complexes undergo two (quasi)reversible redox processes. Temperature-dependent magnetic measurements revealed a high-spin configuration for all sal2trien complexes (S= 2) and gradual spin crossover for sal2bapen complexes from high to low spin (S= 1). The chain length strongly influences the spin crossover, as C18-functionalization stabilizes the low spin state at much higher temperatures than shorter alkyl chains. Moreover, long alkyl chains allow for spontaneous self-assembly of the molecules, which was investigated in single crystals and in Langmuir-films at the air–water interface. Long alkyl chains (C12or C18) as well as a mutual syn-orientation of these molecular recognition sites were required for the Langmuir monolayers to be stable. [ABSTRACT FROM AUTHOR]

New sal2(trien) ligands that contain alkoxy substituents of various length in metaposition of the phenolate entities were coordinated to electronically and magnetically active iron(III) and cobalt(iii) centers. The electrochemical and spectroscopic properties of these amphiphilic complexes are virtually unaffected upon alteration of the alkoxy substituents, thus providing a system in which the physical behavior and the metal-centered chemical activity can be tailored independently. The amphiphilic character has been exploited for preparing Langmuir monolayers at the air–water interface and for constructing Langmuir–Blodgett films, hence allowing for hierarchical assembling of electronically and magnetically active systems. While Langmuir films were stable, transfer onto solid supports was limited, which restricted the magnetic analysis of the Langmuir–Blodgett assemblies. [ABSTRACT FROM AUTHOR]