SuFEx (Sulfur Fluoride Exchange) is a modular, next generation family of click reactions, geared towards the rapid and reliable assembly of functional molecules.

The phase transition is fundamental for understanding physical and chemical properties of materials. The phase transition at the nanometer scale is usually distinguished from that of the bulk counterpart. It is essential to pursue the basic physics involved in the phase transition on nanoscale for applications of nanomaterials. Herein, we have established an analytical thermodynamic model at the nanometer scale to study the phase transition of II-VI semiconductor nanocrystals, and revealed the size-dependent polymorphism behaviors of the phase transition. The physical origin of the size effects on the polymorphism behaviors of II-VI semiconductor nanocrystals was addressed on the basis of the contributions of surface energy and surface stress of nanocrystals to the total Gibbs free energy. It was found that the low surface energy and the small surface stress always predominate the thermal stability of nanostructures with the metastable phase. These results provided new insight into the fundamental understanding of the phase transition of II-VI semiconductor nanocrystals.

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The Pearl River Estuary empties into the South China Sea in southeastern China, and hypoxia is one of the major environmental problems here during summer. It can be caused by coastline, topography, hydrodynamics, tidal dynamics and biological processes (mainly by stratification and oxidation reaction). Since ecological processes are closely related to dynamic processes, we revise and link together both a physical and a biological model to establish a coupled hydrodynamic-ecological numerical model to study the summertime hypoxia. The model simulates physical and biological processes and reproduces the observed hypoxia in the bottom layer in two regions located in west shallow water and around Nei Lingding Island. A low-salinity plume forms after the freshwater drifts offshore. Strong stratification exists in the water body shoreward where the vertical mixing is weak. The salinity front and stratification cause a poor exchange in the vertical direction and greatly influence biological processes for nutrients, phytoplankton, and detritus, which induce the hypoxia occurrence in the bottom layer of the Pearl River Estuary. On the other hand, in two troughs the tide diminishes the strength of stratification and prohibits the large-scale growth of the hypoxia. The physical processes related to topography, run off and tidal mixing regulate the distribution of biological factors and the occurrence of hypoxia.

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