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Poly(n-butyl methacrylate)(PBMA) has been prepared by a suspension polymerization process, and blended with polyacrylonitrile (PAN) in N,N-dimethyl acetamide (DMAc). The rheological analysis results show that the PBMA/PAN blend solution is a typical shear thinning fluid regardless of the PBMA content, and suitable for preparing fibers through a wet spinning process. Moreover, it is observed that with an increased PBMA content, the tensile strength of the blended fibers first slightly increases and then decreases, while the breaking elongation increases, which shows a higher value than that of the PAN fiber. The scanning electron microscope (SEM) and thermogravimetric analysis (TGA) results show that with low content PBMA that is evenly dispersed in the PAN matrix, the heat stability of the blended fibers is remarkably enhanced. The adsorption experiment results show that the addition of PBMA contributes to enhancing the adsorptive capacity of the blended fibers, and the adsorption of the organic solvents on the PBMA/PAN(30-70) blended fibers is two or three times higher than that of the PAN fiber

Using typical structure of asphalt pavement in Harbin area of China, and the formula of generalized friction coefficient between base and surface layers of asphalt pavement in cold area is established.

Through structural characteristics analysis of asphalt pavement in cold area, the generalized formula of friction coefficient between base and surface layers of asphalt pavement in cold area is derived. The formula can quickly calculate the friction coefficient between layers of asphalt pavement.

Based on quantitative analysis to the contacting state between layers of asphalt pavement in cold area, the relationships between generalized friction coefficient and resilient modulus of asphalt mixtures, temperature shrinkage coefficient and temperature have been established.

The findings can enrich the description methods about the contacting state between layers of asphalt pavement, and have a certain theoretical and practical value. Through the application of the formula of generalized friction coefficient between layers, it can provide a technical basis for the asphalt pavement design, construction and maintenance in cold area.