The first unsymmetrical conjugated dendrimer was synthesized using a rather simple approach that involves only one synthon and two sets of reaction conditions. This dendrimer shows broad absorption in the UV and visible range and possesses an intrinsic energy gradient from the outside branches to the core, naturally suggesting itself as a potentially efficient light harvesting material.

The Ulva prolifera green tides in the Yellow Sea, China, which have been occurring since 2007, are a serious environmental problem attracting worldwide attention. Despite extensive research, the outbreak mechanisms have not been fully understood. Comprehensive analysis of anthropogenic and natural biotic and abiotic factors reveals that human activities, regional physicochemical conditions and algal physiological characteristics as well as ocean warming and biological interactions (with microorganism or other macroalgae) are closely related to the occurrence of green tides. Dynamics of these factors and their interactions could explain why green tides suddenly occurred in 2007 and decreased abruptly in 2017. Moreover, the consequence of green tides is serious. The decay of macroalgal biomass could result in hypoxia and acidification, possibly induce red tide and even have a long-lasting impact on coastal carbon cycles and the ecosystem. Accordingly, corresponding countermeasures have been proposed in our study for future reference in ecosystem management strategies and sustainable development policy.

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Poly(phenylenevinylene)s (PPVs) containing rigid oxadiazole units as main chain substituents were synthesized. The electron-deficient oxadiazole moieties are directly attached to the phenyl rings of PPVs to increase the electron-injection properties of the polymers. In addition, the near-orthogonal arrangement of the PPV backbone and the oxadiazole units helps to limit the π-stacking of the emissive units, thus increasing the radiative decay quantum yield and photostability of the polymer. These polymers have shown good electron injection/transport ability and luminescence properties. Single-layer LED devices with the configuration ITO/polymer/Al show external quantum efficiencies up to 0.045%.

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