Experimental study on the buffering effects of urban trees group in dike-break floods.

The process of dike-break flood propagation in typical urban street is highly complex. The presence of buildings and trees groups in urban street profoundly alters the flood dynamics, impacting the drainage capacity of the area. In this study, a generalized sink model representing a typical urban street was established, including trees groups, buildings, sidewalks, and stormwater drainage systems.

Integrated modeling of 2D urban surface and 1D sewer hydrodynamic processes and flood risk assessment of people and vehicles.

In order to accurately simulate the whole urban flooding processes and assess the flood risks to people and vehicles in floodwaters, a 2D-surface and a 1D-sewer integrated hydrodynamic model was proposed in this study, with the module of flood risk assessment of people and vehicles being included. The proposed model was firstly validated by a dual-drainage laboratory experiment on the flood inundation process over a typical urban street, and the relative importance of model parameters and model uncertainties were evaluated using the GSA-GLUE method. Then the model was applied to simulate an actual urban flooding process that occurred in Glasgow, UK, with the influence of the sewer drainage system on flood inundation processes and hazard degree distributions of people and vehicles being comprehensively discussed.

Gold Redox Catalysis through Base-Initiated Diazonium Decomposition toward Alkene, Alkyne, and Allene Activation.

The discovery of photoassisted diazonium activation toward gold(I) oxidation greatly extended the scope of gold redox catalysis by avoiding the use of a strong oxidant. Some practical issues that limit the application of this new type of chemistry are the relative low efficiency (long reaction time and low conversion) and the strict reaction condition control that is necessary (degassing and inert reaction environment). Herein, an alternative photofree condition has been developed through Lewis base induced diazonium activation.

Gold-catalyzed oxidative cross-coupling of terminal alkynes: selective synthesis of unsymmetrical 1,3-diynes.

Gold-catalyzed oxidative cross-coupling of alkynes to unsymmetrical diynes has been achieved for the first time. A N,N-ligand (1,10-Phen) and PhI(OAc)2 were identified as crucial factors to promote this transformation, giving the desired cross-coupled conjugated diynes in excellent heteroselectivity (>10:1), in good to excellent yields, and with large substrate tolerability.

Chemoselective carbophilic addition of α-diazoesters through ligand-controlled gold catalysis.

The chemoselective addition of arenes and 1,3-diketones to α-aryldiazoesters was achieved through ligand-controlled gold catalysis. Unlike a dirhodium catalyst (which promotes C(sp3)-H insertion and cyclopropanation) and a copper catalyst (which catalyzes O-H and N-H insertions), the gold catalyst with an electron-deficient phosphite as the ancillary ligand exclusively gave the carbophilic addition product, thus representing a new and efficient approach to form "carbophilic carbocations", which selectively react with carbon nucleophiles.

Gold-catalyzed intermolecular C-S bond formation: efficient synthesis of α-substituted vinyl sulfones.

A general method for the synthesis of α-substituted vinyl sulfones makes use of a combination of a triazole gold complex and gallium triflate. This efficient CS bond formation between simple terminal alkynes and sulfinic acids provides access to various α-substituted vinyl sulfones.

Ambient gold-catalyzed O-vinylation of cyclic 1,3-diketone: A vinyl ether synthesis.

Gold-catalyzed O-vinylation of cyclic 1,3-diketones has been achieved for the first time, which provides direct access to various vinyl ethers. A catalytic amount of copper triflate was identified as the significant additive in promoting this transformation. Both aromatic and aliphatic alkynes are suitable substrates with good to excellent yields.

Docking and molecular dynamics study on the inhibitory activity of N, N-disubstituted-trifluoro-3-amino-2-propanols-based inhibitors of cholesteryl ester transfer protein.

Extensive studies suggest direct links between cholesteryl ester transfer protein (CETP), high-density lipoproteins-cholesterol level and cardiovascular diseases. Many therapeutic approaches are aimed at the CETP. A series of N, N-disubstituted-trifluoro-3-amino-2-propanol analogues are among the most highly potent and selective inhibitors of CETP described to date.