To improve stability of scorodite,a method of simultaneous synthesis and in-situ coating of scorodite was proposed.Scorodite particles with polyhedral and raspberry-like morphologies were synthesized in an Fe(Ⅱ).As(...To improve stability of scorodite,a method of simultaneous synthesis and in-situ coating of scorodite was proposed.Scorodite particles with polyhedral and raspberry-like morphologies were synthesized in an Fe(Ⅱ).As(Ⅴ).H2O system at 90℃and pH 1.5 by blowing oxygen gas into the system.When the initial Fe/As molar ratio exceeded 1:1,a coating of sulfate-containing iron(hydr)oxides formed on the surfaces of scorodite particles during synthesis.To evaluate the leaching stability of synthesized scorodite samples,toxicity characteristic leaching procedure(TCLP)tests were conducted at pH 4.93 for 60 h,and long-term leaching tests were conducted for 30.40 d within a pH range of 5.40.10.88.The leaching results indicated that the release of arsenic from scorodite was noticeably postponed by the coating,and the average arsenic concentrations in the leaching solutions were as low as 0.12 mg/L in the TCLP tests and lower than 0.5 mg/L in the long-term leaching tests.展开更多
Boron is an attractive candidate of the first wall coating materials in fusion reactors. The behavior of deuterium implanted into boron films has been studied . This paper reports the effect of thin oxygen-containing ...Boron is an attractive candidate of the first wall coating materials in fusion reactors. The behavior of deuterium implanted into boron films has been studied . This paper reports the effect of thin oxygen-containing boron layer on the behavior of deuterium im- planted into boron film by X-ray photoelectron spectroscopy （XPS） and thermal desorption spectroscopy （TDS）.展开更多
The orientation control of graphene overlayers on metal surface is an important issue which remains as a challenge in graphene growth on Ni surface. Here we have demonstrated that epitaxial graphene overlayers can be ...The orientation control of graphene overlayers on metal surface is an important issue which remains as a challenge in graphene growth on Ni surface. Here we have demonstrated that epitaxial graphene overlayers can be obtained by annealing a nickel carbide covered Ni（111） surface using in situ surface imaging techniques. Epitaxial graphene islands nucleate and grow via segregation of dissolved carbon atoms to the top surface at about 400 ℃. This is in contrast to a mixture of epitaxial and non-epi- taxial graphene domains grown directly on Ni（111） at 540 ℃. The different growth behaviors are related to the nucleation dynamics which is controlled by local carbon densities in the near surface region.展开更多
基金Project(51574285)supported by the National Natural Science Foundation of China
文摘To improve stability of scorodite,a method of simultaneous synthesis and in-situ coating of scorodite was proposed.Scorodite particles with polyhedral and raspberry-like morphologies were synthesized in an Fe(Ⅱ).As(Ⅴ).H2O system at 90℃and pH 1.5 by blowing oxygen gas into the system.When the initial Fe/As molar ratio exceeded 1:1,a coating of sulfate-containing iron(hydr)oxides formed on the surfaces of scorodite particles during synthesis.To evaluate the leaching stability of synthesized scorodite samples,toxicity characteristic leaching procedure(TCLP)tests were conducted at pH 4.93 for 60 h,and long-term leaching tests were conducted for 30.40 d within a pH range of 5.40.10.88.The leaching results indicated that the release of arsenic from scorodite was noticeably postponed by the coating,and the average arsenic concentrations in the leaching solutions were as low as 0.12 mg/L in the TCLP tests and lower than 0.5 mg/L in the long-term leaching tests.
文摘Boron is an attractive candidate of the first wall coating materials in fusion reactors. The behavior of deuterium implanted into boron films has been studied . This paper reports the effect of thin oxygen-containing boron layer on the behavior of deuterium im- planted into boron film by X-ray photoelectron spectroscopy （XPS） and thermal desorption spectroscopy （TDS）.
基金Acknowledgments This work was supported by the National Natural Science Foundation of China （21373208, 91545204, and 21321002）, the National Basic Research Program of China （2016YFA0200200, 2013CB834603, and 2013CB933100）, and the Strategic Priority Research Program of the Chinese Academy of Sciences （XDB 17020200）. The authors are grateful for the support for Nano-X from Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences （SINANO）.
文摘The orientation control of graphene overlayers on metal surface is an important issue which remains as a challenge in graphene growth on Ni surface. Here we have demonstrated that epitaxial graphene overlayers can be obtained by annealing a nickel carbide covered Ni（111） surface using in situ surface imaging techniques. Epitaxial graphene islands nucleate and grow via segregation of dissolved carbon atoms to the top surface at about 400 ℃. This is in contrast to a mixture of epitaxial and non-epi- taxial graphene domains grown directly on Ni（111） at 540 ℃. The different growth behaviors are related to the nucleation dynamics which is controlled by local carbon densities in the near surface region.
