This work focuses on studying a novel polymer/nanocrystal multilayer for the fabrication of donor and accepter typed photovoltaic device. Highly luminescent anionic CdTe nanocrystals were prepared by aqueous synthesis method using 3-mercaptopropionic acid as stabilizer. The resultant CdTe served as electron acceptor and poly(p-phenylene vinylene) (PPV) was used as electron donor. Through the electrostatic interactions between cationic PPV precursor poly(p-xylene tetrahydrothiophenium chloride) and anionic poly(sodium4-styrenesulfonate) (PSS), PPV/PSS complex was fabricated on the surface of pretreated quartz substrate by layer-by-layer electrostatic self-assembly method. UV-Vis spectrum shows that PSS in the PPV/PSS complex make PPV precursors thermally convert into PPV at a lower temperature and less time. PPV/ PSS/PPV/CdTe multilayer were fabricated on the surface of quartz substrate by electrostatic self-assembly method. The surface of the polymer/CdTe complex is flat, which was characterized by atomic force microscopy (AFM). UV-Vis spectrum of the polymer/CdTe complex shows that the absorbance increases with the increase of the number of deposition cycles. In the same way, PPV/PSS/PPV/CdTe multilayer were fabricated on the surface of ITO substrate disposed by the poly(3,4- ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS). The resultant polymer/ CdTe complex is measured under AM1.5G simulated solar illumination with 100mW•cm-2 in air. The open circuit current density (VOC) and short circuit current density (JSC) of the polymer/CdTe complex are 0.60 V and 0.305 mA•cm-2 which are better than PPV or CdTe nanocrystal individual. This could be ascribed to interfacial hole-electron converter between the conjugated polymer layer and CdTe nanocrystal layer. Besides, the photovoltaic properties of PPV/CdTe complex can be improved by controlling the layers of PPV/ CdTe nanocrystals complex on the ITO substrate.

Southwest area of china is the zone of the transmission lines which often happens icing disaster. It is also an earthquake-prone area, also influenced by the interaction between ice and earthquake. This article uses the finite element method (fem), establishing three-dimensional model for steel towers in southwest china, to analyze the dynamic performance of the ice condition and the analysis of seismic action. The aim is to get internal forces for steel towers under the action of earthquake and deformation law along with the change of ice thickness.

This study presents the development of a probability model for pavement slippage failure. A measurement method for a tack coat residual application rate in a field core through binder extraction was developed and verified. It was found that implementing a measurement method for tack coat quality acceptance is feasible. Pavement investigations were performed on two slippage failure cases in Indiana and confirmed that the residual application rates of slippage failed sections were significantly lower than those of non-failed sections. A slippage failure probability model in terms of residual application rates was developed through binary logistic regression analysis. The model can be used to determine appropriate residual application rates in consideration of its uniformity from a distributor and to develop tack coat specifications based on slippage failure probability.

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