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采用了恰当的衔接手法，层次清晰；句式变化多样，句法方面做的很棒；作者高级词汇使用比较准确，词汇表达较丰富，但仍需增加词汇积累。
As illustrated in Table 4, the conversion of SO, the yield and the selectivity towards SC were improved with an enhancement in the pressure of CO2 below 8 MPa, and the maximum selectivity at 89.1% and yield at 87.1% were obtained at 8 MPa (entry 4), respectively. The unique properties appearing near the critical point are probably responsible for this positive effect on the rate and the selectivity [3]. The variation of density around the critical point generally causes a change in chemical and/or physical equilibrium. Similar results with a maximum selectivity near the critical pressure of CO2 were reported elsewhere [9,44]. In addition, two phases such as gas and liquid phase are generally observed in the reactions involving supercritical CO2 [43]. The upper gas and the lower liquid are mainly composed of CO2 and substrate, respectively. Both the concentration of CO2 in the liquid phase and the solubility of substrate in gas phase increase with enhancing the pressure of CO2. The former is beneficial to the reaction while the latter is not [45]. Therefore, the competition of these contradictory factors leads to maximal SC yield at 8 MPa.
