Wheat lodging results in great losses of wheat production about 10%~30% every year. It is very important to study the lodging and to find new way to improve the quality of wheat stalks and its anti-lodging characteristics. The study about the changing of wheat stem mechanical properties with the elastic modulus and stem structure is carried on the basement of theoretical model, experimental improvement, and finite element method. Results show that the stem is more difficult to lodge if the ratio is bigger, which can be calculated through elastic modulus multiplying wall thickness and divided by diameter.

Eethyl levulinate (EL) can be produced by direct conversion of glucose in ethanol medium. Both sulfuric acid and solid acid catalyst (USY) can be used as effective acid catalyst. The maximum EL yields were almost same. However, the usage of USY is helpful to limit the diethyl ether (DEE) production efficiently for recycling of ethanol. In ethanol/water mixed medium, water addition has significant effect on the products distribution. EL yield decreased obviously in water-rich medium. Meanwhile, the amount of DEE decreased with the increase of water addition. However, water addition has the opposite effect on the humic solid formation, and more humic solid can be formed in water-rich medium.

The anaerobic fermentation characteristics of green and dried corn straw pretreated by steam explosion method were investigated. The steam pressure and retention time were 1.0Mpa and 90s, TS of fermentation liquid were 2% and 4%. It was shown that the fermentation cycle of green straw is shorter than that of the dried one by 4-7 days, the gas productivity of green straw is 220 mL/gVS, which is higher than that of dried one (153 mL/gVS) while TS is 2%, but there is no significant difference between the green and dried corn straw while TS is 4%, the average methane content in biogas produced from green straw is slightly less than that of the dried one.

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The alkaline-pretreated wheat straw was used as raw materials, and the fed-batch simultaneous saccharification and fermentation (SSF) process for ethanol production with higher substrate loading (up to 16% (w/v)) was investigated. Firstly, the Fed-batch SSF with different feeding strategy was optimized. The highest ethanol concentration reached to 37.9 g/L with an initial substrate loading of 10% (w/v), and equal substrate addition (3%) at 8h and 16h respectively. Then the effects of Tween-20 were also investigated. The results showed that Tween-20 addition with 2.0 g/L can improved the ethanol production. Furthermore, a nonisothermal fed-batch SSF was proposed, and the ethanol concentration of 41.5 g/L, corresponds to 81.0 % of the theoretical yield was achieved within 72 h.