fig3
![Dynamic evolution of HZSM-5 zeolite framework under steam treatment](https://image.oaes.cc/6107d319-be87-4dc6-8ef5-642c7c0df1ae/cs4055.fig.3.jpg)
Figure 3. (A) 1H MAS NMR spectra of HZSM-5 before and after steam treatment; (B) concentrations of different hydroxyl groups by quantifying and fitting the quantitative 1H MAS NMR spectra; (C) FTIR spectra of the OH vibration region of HZSM-5 before and after steam treatment; (D) 1H-27Al S-RESPDOR spectra of HZSM-5-300-2 sample with a recoupling time of 0.6 ms. S and S’ denote the 1H spectrum without and with 27Al irradiation, respectively; ΔS is the difference spectrum obtained by S-S’.