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The effects of graphene, layered bimetallic hydroxides (LDHs) and graphene compounded LDHs on the physical properties, thermal oxygen aging resistance and ultraviolet oxygen aging resistance of SBS modified asphalt were studied, and the change of chemical structure of the modified asphalts before and after aging was analyzed by Fourier transform infrared spectroscopy (FTIR). The results showed that the high-temperature and anti-aging properties of SBS modified asphalt could be improved by adding graphene, LDHs and graphene compounded LDHs. Compared with graphene and LDHs, graphene compounded LDHs could simultaneously reduce the changes of softening point and viscosity of SBS modified asphalt before and after thermal-oxidative and ultraviolet-oxidative aging, and increase the ductility and penetration retention. FTIR analysis showed that the carbonyl index change rate and carbon-carbon double bonds index change rate of SBS modified asphalt mixed with graphene compounded LDHs were the smallest before and after aging, indicating that graphene compounded LDHs had a better effect on improving the aging resistance of SBS modified asphalt. [ABSTRACT FROM AUTHOR]

In view of the evaluation of fundus image segmentation, a new evaluation method was proposed to make up insufficiency of the traditional evaluation method which only considers the overlap of pixels and neglects topology structure of the retinal vessel. Mathematical morphology and thinning algorithm were used to obtain the retinal vascular topology structure. Then three features of retinal vessel, including mutual information, correlation coefficient and ratio of nodes, were calculated. The features of the thinned images taken as topology structure of blood vessel were used to evaluate retinal image segmentation. The manually-labeled images and their eroded ones of STARE database were used in the experiment. The result showed that these features, including mutual information, correlation coefficient and ratio of nodes, could be used to evaluate the segmentation quality of retinal vessel on fundus image through topology structure, and the algorithm was simple. The method is of significance to the supplement of traditional segmentation evaluation of retinal vessel on fundus image.