可逆性

The formal potentials in cyclic voltammograms of these 3+ valence complexes are followed: Co〓-TPPS (-0.08V )＞Fe〓TPPS (-0.14V)＞Mn〓-TPPS (-0.23V). The electrochemical reaction of Mn〓-TPPS is reversible, and both of Co〓-TPPS and Fe〓-TPPS are quasi-reversible. The standard heterogeneous rate constants of Co〓-TPPS and Fe〓-TPPS were determined to be 1. 4×10〓cm/s and 1.4×10〓cm/s respectively. The rates of electrode reaction are as followed: Mn〓-TPPS＞Co〓-TPPS＞Fe〓-TPPS, e.i. Mn〓-TPPS is the most easily oxidized by the dissolved oxygen, and Fe〓-TPPS is oxidized slower than Co〓-TPPS. Ni〓-TPPS can not be oxidized. It is considered that oxygen plays an important role in the valence change of central metal atom and the rate of electron transfer in some metalloporphyrins.

三价金属卟啉络合物在循环伏安图上可得到三价到二价的还原和氧化响应，电极电位从大到小排列为：Co〓-TPPS(-0.08V)＞Fe〓-TPPS(-0.14V)＞Mn〓-TPPS(-0.23V)，电极反应可逆性也不相同，Mn〓-TPPS是可逆过程，Co〓-TPPS、Fe〓-TPPS是准可逆过程，实验测得Co〓-TPPS的标准电极反应速率常数ks＝1.4×10〓cm/s，Fe〓-TPPS的ks＝1.4×10〓cm/s，电极反应的速率从大到小为：Mn〓-TPPS＞Co〓-TPPS＞Fe〓-TPPS，即Mn〓-TPPS最容易被溶解氧所氧化，Fe〓-TPPS被氧化的速度最慢，Ni〓-TMPyP不能被氧化，因此我们认为溶解氧对金属卟啉中心离子的价态和电子转移速率起着重要作用。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。