In the present study, two novel fully biobased benzoxazines were synthesized using modified products of rosin, dehydroabietylamine, guaiacol, 4-methylumbelliferone, and paraformaldehyde. The chemical structures of DM (dehydroabietylamine, 4methylumbelliferone) and DG (dehydroabietylamine, guaiacol) were characterized by Fourier transform infrared spectroscopy (FTIR), 1 H nuclear magnetic resonance (NMR) and 13 C NMR spectra, dimensional nuclear magnetic and high-resolution mass spectrometry. The curing process of DM and DG was monitored by differential scanning calorimetry and in situ FTIR. The results demonstrated that the corresponding polymers PDM and PDG had high thermal stability. In addition, they had low dielectric constants below 3.30 at 25 °C and 1 kHz condition. Water contact angle measurements, OPC-time curves, and Tafel plots of PDG and PDM were also studied. The results showed that anticorrosion performances of PDG and PDM were stable during the immersion process and had strong abilities as shield corrosive media. Therefore, these two benzoxazine resins based on dehydrobietylamine may have potential applications in many fields.

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A hollow Silicalite-1-HZSM-5 zeolite capsule embedded with Mo nanoparticles was designed, enhancing the catalytic performance of methane dehydroaromatization to benzene.

A two-step method consisting of acid leaching and base leaching was developed and applied to create hierarchical pores on a general microporous Y zeolite. Characterization with BET and TEM on the texture, morphology and structure of the prepared hierarchical Y zeolite confirmed the coexistence of mesopores with zeolitic walls. The analysis results showed that the mesopore surface area and pore volume of the hierarchical zeolite Y (Y-ABx, A: acid leaching, B: base leaching, "x" represents for base leaching time) increased with increasing the base leaching time. The hierarchical zeolite Y supported Co as catalysts were employed to catalyze the hydrogenation of carbon monoxide to form hydrocarbons through Fischer-Tropsch synthesis (FTS) reaction. The CO conversion and C 5-11 selectivity on Co/Y-ABx catalysts increased significantly compared with those on the pristine Y supported Co catalyst. The isoparaffin selectivity of Co/Y-AB4 catalyst reached up to 52.3 % and middle hydrocarbons became the main FTS products due to the optimized hydrocracking and isomerization function afforded by the hierarchical zeolite Y with the strong Brønsted acid/Lewis acid (B/L) ratio and textural property.

A novel dual gold/photoredox-catalyzed bis-arylative cyclization of chiral homopropargyl sulfonamides with diazonium salts has been developed, allowing the facile synthesis of various enantioenriched 2,3-dihydropyrroles in generally moderate to good yields with excellent enantioselectivities under very mild conditions without using any strong oxidants. The reaction is proposed to undergo an Au/Au redox cycle promoted by visible-light photoredox catalysis.

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