China has a rich genetic resource in its 34 domestic duck breeds. In order to detect the genetic diversity and explore the origin of these indigenous duck populations, the mitochondrial DNA (mtDNA) control region was sequenced and analyzed for 208 individual ducks, including 22 domestic breeds, wild Mallards ducks, Eastern spot-billed ducks, White Muscovy ducks, and Black Muscovy ducks. The haplotype diversity (Hd) was 0.653 and the average nucleotide diversity (Pi) was 0.005, indicating moderate genetic diversity. Sixty haplotypes were detected, and the maximum-likelihood (ML) phylogenetic tree and median-joining (MJ) network were generated from the sequence analyses. In this study, haplotypes from the Mallard duck (Anas platyrhynchos) were detected in most of the Chinese domestic duck breeds. In addition, the Eastern spot-billed duck (A. zonorhyncha) H8 haplotype was detected in two duck breeds. Only two haplotypes were found in Muscovy ducks, suggesting low genetic diversity within this population. The sequence and haplotype analyses revealed that both A. platyrhynchos and A. zonorhyncha contributed to the evolution of domestic ducks in China.

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Four zinc-rich coatings were applied onto steel substrate and then placed in neutral salt spray for 4000 h in order to study the anti-corrosion performance of the coatings. The results showed that the samples with two kinds of the coatings were more seriously eroded than the others. The reasons could be that the zinc particles were dispersed inhomogeneous in the binder and the zinc content was very lower than 96 wt. % obtained through the analysis of Scanning Electron Microscope and Differential Scanning Calorimetry.

In order to explore the characteristics of electric bicycles at urban intersections, the model between speed and density was developed. Coordinates of electric bicycles were obtained based on photogrammetry, and 85% riding width was proposed to be the design width through the analysis of relationship between cycle volume and riding width. In addition, the model between speed and density were obtained through data fitting, which was almost a linear function. The speed and riding width can be obtained through the model on the basis of the volume of electric bicycles, which can provide theoretical support for the control and design of urban intersections..