Tunable color center lasers making use of electron trapping defects such as F A and F + 2 like centers in alkali halide crystals can deliver broadly tunable power over the near infrared 0.8—4.0μm range.The tunable r...Tunable color center lasers making use of electron trapping defects such as F A and F + 2 like centers in alkali halide crystals can deliver broadly tunable power over the near infrared 0.8—4.0μm range.The tunable range and their impressive feature of narrow linewidth make these solid state lasers important to molecular spectroscopy,pollution detection,fiber optics communication and other scientific research fields.The( F + 2) H center consisting of an F + 2 center and an neibouring O 2- ion,is one of the most important color centers.In this paper,we will study the preparation,absorption and emission spectra of the ( F + 2) H center in mixed crystal KCl KBr∶OH -. Single crystals of KCl,KBr and different compositions of KCl x Br 1-x solid solutions are growtn with 0.1mol%—0.3mol% KOH in the melt by the Czochralski technique in air.展开更多
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
文摘Tunable color center lasers making use of electron trapping defects such as F A and F + 2 like centers in alkali halide crystals can deliver broadly tunable power over the near infrared 0.8—4.0μm range.The tunable range and their impressive feature of narrow linewidth make these solid state lasers important to molecular spectroscopy,pollution detection,fiber optics communication and other scientific research fields.The( F + 2) H center consisting of an F + 2 center and an neibouring O 2- ion,is one of the most important color centers.In this paper,we will study the preparation,absorption and emission spectra of the ( F + 2) H center in mixed crystal KCl KBr∶OH -. Single crystals of KCl,KBr and different compositions of KCl x Br 1-x solid solutions are growtn with 0.1mol%—0.3mol% KOH in the melt by the Czochralski technique in air.
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.
