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Raspberry subcultured tissue seedlings were used as test materials for the effect of different concentrations of graphene on the growth of raspberry seedlings and the development of adventitious roots. The graphene was characterized by a laser particle size analyzer, STEM, TEM, XPS and Raman spectroscopy. A root analysis system and SEM were used to systematically characterize the seedling height, root length, root specific surface area, number of branches, number of root tips and root micromorphology, thus determining the optimum concentration of graphene for the growth of raspberry tissue culture seedlings. The results showed that with increasing graphene concentration, the seedling height, root length, root tip number and root specific surface area of the seedlings all showed a trend of first increasing and then decreasing. The optimum concentration of graphene was 2 mg·L-1, the seedling height of tissue culture seedlings was 1.46 times that of the control group, and the root length, specific surface area, number of root tips and their bifurcation number were about twice that of the control group.

In order to study the effect of minerals on biomass pyrolysis, experiments on pyrolysis of corn straw with different pretreatment methods were performed by using a thermogravimetric analyzer(TGA) coupled with a Fourier transform infrared( FTIR) spectrometer. The pretreatment methods included water washing and acid washing. The experimental results show that acid washing can remove almost all K(+) and 78% of Ca(2+) while water washing only removes most of K(+). The existence of K(+) and Ca(2+) obviously favors the formation of compounds containing carbonyl groups and CO(2), but it will decrease the yields of compounds containing C-O-C groups. However, the formation of H(2)O, CO and CH(4) are slightly affected by the removal of inorganic ions. With regard to the structure of the metal ions-adsorbed cellulose characterized by IR analysis, it can be considered that there is an "ion force" between metal ions and cellulosic biomass. The results of thermal kinetic analysis show that this force can make the reaction activation energy of the biomass pyrolysis decrease. A new mechanism is proposed for explaining the effect of inorganic ions on cellulose pyrolysis.