## 3 Results and Discussion  
### Results of Ultimate Analysis and Proximate Analysis  
The results of ultimate analysis and proximate analysis are listed in Table 1, as the properties of the biomass samples. As seen in Table 1, the contents of the major elements in agricultural straw and wood are quite different. The contents of C in wood are higher than in agricultural straw. Conversely, the contents of N and S in wood are significantly lower than in agricultural straw. The contents of O in agricultural straw are lower than in wood except for soya and Ph. The contents of C, O, and H in rice straw are lower than other biomass samples. The sum of five major elements are lower than 85% for rice straw, while that of other biomass samples are higher than 90%, especially for wood. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Biomass Samples**} & \multicolumn{4}{c}{**Ultimate Analysis (wt.\%)**} & \multicolumn{4}{c}{**Proximate Analysis (wt.\%)**} \\ \cline{2-10}  & **C** & **O** & **H** & **N** & **S** & **VM** & **FC** & **Ash** & **M** \\ \hline Soya & 41.31 & 45.61 & 6.40 & 0.870 & 0.319 & 74.61 & 19.81 & 5.58 & 10.61 \\ Wheat & 42.48 & 43.69 & 6.21 & 0.590 & 0.470 & 75.61 & 15.30 & 9.09 & 7.51 \\ Corn & 41.66 & 43.86 & 6.14 & 0.587 & 0.342 & 71.59 & 20.19 & 8.21 & 10.16 \\ Rice & 36.72 & 40.41 & 5.83 & 0.527 & 0.538 & 66.43 & 14.89 & 18.68 & 8.93 \\
**Average** & **40.54** & **43.39** & **6.14** & **0.644** & **0.417** & **72.06** & **17.55** & **10.39** & **9.30** \\
**SD 1** & **2.60** & **2.17** & **0.24** & **0.154** & **0.104** & **4.12** & **2.84** & **5.72** & **1.39** \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The ultimate analysis and proximate analysis of biomass samples. Figure 1: Schematic diagram of the fire test room and the experimental setup. The average contents of C, H, and O in agricultural straw are 40.54% \(\pm\) 2.60%, 6.14% \(\pm\) 0.24%, and 43.39% \(\pm\) 2.17%, respectively, while that in wood are 46.80% \(\pm\) 0.73%, 6.18% \(\pm\) 0.13%, and 44.67% \(\pm\) 1.22%, respectively. The average contents of C, H, and O are all higher in wood than in agricultural straw. The contents of C, H, and O in wood are in a narrow range. The results of agricultural straw are also similar except for rice straw. The Van Krevelen diagram in Figure 2 shows the elemental compositional differences between biomass samples of wood and agricultural straw. The ultimate analysis results of biomass samples are similar to the results of other researchers [36; 37; 38]. Different kinds of biomass have different contents of VM, FC, and ash [25; 26; 37; 36]. Pi has the highest content of VM but the lowest content of ash. The contents of VM in rice straw and Ph are lower than the other biomass samples, while the contents of ash are higher than the other biomass except for Ph. The corn straw has the highest content of FC, while P1 has the lowest. The average contents of VM, FC, and ash in agricultural straw are 72.06% \(\pm\) 4.12%, 17.55% \(\pm\) 2.84%, and 10.39% \(\pm\) 5.72%, respectively, while that in wood are 76.42% \(\pm\) 6.87%, 13.50% \(\pm\) 1.64%, and 10.08% \(\pm\) 7.80%, respectively. The average contents of FC and ash are lower in wood than in agricultural straw, while that of VM is higher in wood than in agricultural straw. The content distributions of VM, FC, and ash are dispersed in the large range. The contents of FC in biomass samples are mainly in the range of 10-20%. The contents of VM and ash are in the range of 60-85% and 0-20%, respectively. The contents of VM and ash in biomass samples are in the relationship of a negative correlation (r\({}^{2}\) = 0.81), and the Pearson's correlation coefficient (PCC) is \(-\)0.89103, as shown in Figure 3. The char and alkali metals possessed a catalytic effect on the thermal degradation of biomass during pyrolysis [39], with ash of abundant alkaline elements produced [40]. The total liquid and organic yields (representation of VM) increase, while ash composition decrease.