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Lignin as the main component of black liquor is generally employed to modify aliphatic superplasticizer (AFS). However, the modification effect is hard to evaluate correctly due to the uncertain molecular structure of lignin and the disturbance from the complexity of black liquor compositions. In this paper, the purified lignin via acid precipitation from straw black liquor is used to modify AFS. The modified AFS named as LAFS for short presents lower molecular mass than AFS. It is assumed that it is due to the single active site of guaiacol segments in lignin by which lignin graft modifies AFS in virtue of methylolation reaction. In order to verify this assumption, guaiacol and dihydro eugenol as the typical segments of lignin macromolecule were selected, respectively, as the simplified model compounds of lignin to modify AFS, and corresponding products are abbreviated in GAFS and DAFS. Both GAFS and DAFS show the lower molecular mass than unmodified AFS. FTIR and TG-DTG analyses prove that lignin is successfully grafted onto AFS. The graft modification of lignin results in a decrease in electrostatic epulsion, but an enhanced steric hindrance. Therefore, although the replacement rate of lignin in LAFS was about 23.3%, the dispersion performance was only slightly affected.

Shift-share analysis is an extensively used mathematical method for research on regional economy and industrial structure at home and abroad. It owns unique advantages as regard to synthesis and dynamics. Nevertheless, current studies at home mainly rest on the application of traditional relative static model with no consideration of time factor. With the introduction of dynamic thinking, this paper constructs dynamic time series to expand traditional model. It not only reveals the contribution each growth component makes to total growth, but exhibits the law of development of each growth component on time series. Through the comparative analysis of traditional shift-share method and the developed dynamic model, the later possesses advantages in three aspects: time span, analysis result and range of application. The dynamic model not only reveals the variation characteristics of each industrial department among various provinces, but offers quantitative analysis on industrial structure and varying trend of competitiveness from year to year. It facilitates the discovery of evolution patterns in six provinces in central China. The "Twelfth Five-Year Plan" period in China is meanwhile a key phase to achieve the "Rise of Central China"; the results of this paper provide scientific basis and direction for central China industrial structure adjustment.