Two kinds of simulated concrete pore solutions(SPSs) were treated with different amounts of synthetic calcium silicate hydrate(C-S-H). The variation of the [Cl^-]/[OH^-] ratio in SPS was measured and the corrosion...Two kinds of simulated concrete pore solutions(SPSs) were treated with different amounts of synthetic calcium silicate hydrate(C-S-H). The variation of the [Cl^-]/[OH^-] ratio in SPS was measured and the corrosion susceptibility of carbon steel in the SPS was investigated with potentiodynamic polarization, EIS and weight lose tests. The experimental results showed that for the SPS at p H 12.5, as the amount of C-S-H increases, the [Cl^-]/[OH^-] ratio increases thereby causing an increase in the corrosion susceptibility of the steel. While for the SPS at p H 9.7, with increasing C-S-H amount, the drop amplitudes of both [Cl^-]/[OH^-] ratio and steel corrosion rate first decrease and then increase, and a 3% C-S-H addition shows the best inhibition effect. XPS results demonstrate that after C-S-H treating in p H 12.5 SPS the [Fe^(3+)]/[Fe^(2+)] ratio in the film on steel surface is reduced while in p H 9.7 SPS the [Fe^(3+)]/[Fe^(2+)] ratio is increased. The different effects of the C-S-H amount on the two SPSs and the steel corrosion behavior result from the influences of C-S-H on the SPS p H, which is related to the composition of the SPS.展开更多
在高一化学教材必修(2)第二章第一节"化学能与热能"里有一个这样的演示实验:将约20 g Ba(OH)2·8H2O晶体研细后与约10 g NH4Cl晶体一起放入烧杯中,并将烧杯放入滴有几滴水的玻璃片或小木块上,用玻璃棒快速搅拌闻气味,用手触...在高一化学教材必修(2)第二章第一节"化学能与热能"里有一个这样的演示实验:将约20 g Ba(OH)2·8H2O晶体研细后与约10 g NH4Cl晶体一起放入烧杯中,并将烧杯放入滴有几滴水的玻璃片或小木块上,用玻璃棒快速搅拌闻气味,用手触摸杯壁下部,试着用手拿起烧杯,观察现象。一、实验存在的问题1.实验成功的关键是小烧杯与下面的玻璃片要粘结在一起,否则会被认为不成功。展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51171014 and 51210001)
文摘Two kinds of simulated concrete pore solutions(SPSs) were treated with different amounts of synthetic calcium silicate hydrate(C-S-H). The variation of the [Cl^-]/[OH^-] ratio in SPS was measured and the corrosion susceptibility of carbon steel in the SPS was investigated with potentiodynamic polarization, EIS and weight lose tests. The experimental results showed that for the SPS at p H 12.5, as the amount of C-S-H increases, the [Cl^-]/[OH^-] ratio increases thereby causing an increase in the corrosion susceptibility of the steel. While for the SPS at p H 9.7, with increasing C-S-H amount, the drop amplitudes of both [Cl^-]/[OH^-] ratio and steel corrosion rate first decrease and then increase, and a 3% C-S-H addition shows the best inhibition effect. XPS results demonstrate that after C-S-H treating in p H 12.5 SPS the [Fe^(3+)]/[Fe^(2+)] ratio in the film on steel surface is reduced while in p H 9.7 SPS the [Fe^(3+)]/[Fe^(2+)] ratio is increased. The different effects of the C-S-H amount on the two SPSs and the steel corrosion behavior result from the influences of C-S-H on the SPS p H, which is related to the composition of the SPS.
文摘在高一化学教材必修(2)第二章第一节"化学能与热能"里有一个这样的演示实验:将约20 g Ba(OH)2·8H2O晶体研细后与约10 g NH4Cl晶体一起放入烧杯中,并将烧杯放入滴有几滴水的玻璃片或小木块上,用玻璃棒快速搅拌闻气味,用手触摸杯壁下部,试着用手拿起烧杯,观察现象。一、实验存在的问题1.实验成功的关键是小烧杯与下面的玻璃片要粘结在一起,否则会被认为不成功。