The newly prepared water-soluble naphthalene tweezer 2a and anthracene clip 4a (substituted both with lithium methanephosphonate groups in the central spacer unit) undergo an unexpected self-assembly in aqueous solution. The highly ordered intertwined structures of the self-assembled dimers [2a]2 and [4a]2 were elucidated by quantum chemical 1H NMR shift calculations. 2a and 4a form extremely stable host-guest complexes with N-methylnicotinamide 8 in methanol and water as well. According to the thermodynamic parameters determined by 1H NMR titration experiments at various temperatures the self-assembly of 2a and 4a and their strong binding to NMNA 8 observed in aqueous solution are enthalpy driven (DeltaH << 0); the enthalpic driving force is partially compensated by an unfavorable entropy (TDeltaS < 0). Self-assembly and the host-guest binding are therefore beautiful examples of the nonclassical hydrophobic effect.

During the past decades, research in self-healing materials has focused on the improvement in the mechanical properties, making stronger materials, able to bear increasing solicitations. This strategy proved to be costly and in some cases inefficient, since materials continue to fail, and maintenance costs remained high. Instead of preparing stronger materials, it is more efficient to prepare them to heal themselves, reducing repairing costs and prolonging their lifetime. Several different self-healing strategies, applied to different material classes, have been comprehensively studied. When new materials are subject of research, the attention is directed into the formulations, product processing and scale-up possibilities. Efforts to measure self-healing properties have been conducted considering the specific characteristics of each material class. The development of comprehensive service conditions allowing a unified discussion across different materials classes and the standardization of the underlying quantification methods has not been a priority so far. Until recently, the quantification of self-healing ability or efficiency was focused mostly on the macroscale evaluation, while micro and nanoscale events, responsible for the first stage in material failure, received minor attention. This work reviews the main evaluation methods developed to assess self-healing and intends to establish a route for fundamental understanding of the healing phenomena

Among latex-producing plants, mainly the latex of Hevea brasiliensis has been studied in detail so far, while comprehensive comparative studies of latex coagulation mechanisms among the more than 20,000 latex-bearing plant species are lacking. In order to give new insights into the potential variety of coagulation mechanisms, the untreated natural latices of five latex-bearing plants from the families Euphorbiaceae, Moraceae and Campanulaceae were visualised using Cryo-SEM and their particle size compared using the laser diffraction method. Additionally, the laticifers of these plants species were examined in planta via Cryo-SEM. Similar latex particle sizes and shape were found in Ficus benjamina and Hevea brasiliensis. Hence, and due to other similarities, we hypothesize comparable, mainly chemical, coagulation mechanisms in these two species, whereas a physical coagulation mechanism is proposed for the latex of Euphorbia spp. The latter mechanism is based on the huge amount of densely packed particles that after evaporation of water build a large surface area, which accelerates the coagulation procedure.

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The broad signals in D 2 O could not be assigned by C,H-COSY. Therefore, the assignment of the signals was made by comparison with the signals in CD 3 OD. * The broad signals in D 2 O could not be assigned by C,H-COSY. Therefore, the assignment of the signals was made by comparison with the signals in CD 3 OD.