Removal of X-ray-induced carbon contamination on beamline optics was studied using radio-frequency plasma with an argon/hydrogen(Ar/H_2) mixture. Experiments demonstrated that the carbon removal rate with Ar/H_2 plasm...Removal of X-ray-induced carbon contamination on beamline optics was studied using radio-frequency plasma with an argon/hydrogen(Ar/H_2) mixture. Experiments demonstrated that the carbon removal rate with Ar/H_2 plasma was higher than that with pure hydrogen or argon. The possible mechanism for this enhanced removal was discussed. The key working parameters for Ar/H_2 plasma removal were determined, including the optimal vacuum pressure, gas mixing ratio, and source power. The optimal process was performed on a carbon-coated multilayer, and the reflectivity was recovered.展开更多
In this paper, the transparent hard diamond-like carbon (DLC) films were deposited on glass substrate by magnetic confined radio-frequency plasma chemical vapor deposition. The structure of films was studied by Raman ...In this paper, the transparent hard diamond-like carbon (DLC) films were deposited on glass substrate by magnetic confined radio-frequency plasma chemical vapor deposition. The structure of films was studied by Raman spectra and X-ray photoelectron spectra (XPS), the transmittance of films by Spectrophotometer. The mechanism of the influence of films structure on transmittance of the films was discussed. The results show that the thickness of films was lower than 100nm, and the transmittance was over 90% in 380-780 nm region. Discussion in theory on the influence of film structure on transmittance was correspondence to experiment results.展开更多
The production of high quality single-walled carbon nanotubes(SWCNTs)on a bulk scale has been an issue of considerable interest.Recently,it has been demonstrated that high quality SWCNTs can be continuously synthesize...The production of high quality single-walled carbon nanotubes(SWCNTs)on a bulk scale has been an issue of considerable interest.Recently,it has been demonstrated that high quality SWCNTs can be continuously synthesized on large scale by using induction thermal plasma technology.In this process,the high energy density of the thermal plasma is employed to generate dense vapor-phase precursors for the synthesis of SWCNTs.With the current reactor system,a carbon soot product which contains approximately 40 wt%of SWCNTs can be continuously synthesized at the high production rate of~100 g/h.In this article,our recent research efforts to achieve major advances in this technology are presented.Firstly,the processing parameters involved are examined systematically in order to evaluate their individual inuences on the SWCNT synthesis.Based on these results,the appropriate operating conditions of the induction thermal plasma process for an effective synthesis of SWCNTs are discussed.A characterization study has also been performed on the SWCNTs produced under the optimum processing conditions.Finally,a mathematical model of the process currently under development is described.The model will help us to better understand the synthesis of SWCNTs in the induction plasma process.展开更多
基金supported by the National Nature Science Foundation of China(No.61404139)the National Science and Technology Major Project(No.2012ZX0270 2001-005)the State Key Laboratory of Applied Optics
文摘Removal of X-ray-induced carbon contamination on beamline optics was studied using radio-frequency plasma with an argon/hydrogen(Ar/H_2) mixture. Experiments demonstrated that the carbon removal rate with Ar/H_2 plasma was higher than that with pure hydrogen or argon. The possible mechanism for this enhanced removal was discussed. The key working parameters for Ar/H_2 plasma removal were determined, including the optimal vacuum pressure, gas mixing ratio, and source power. The optimal process was performed on a carbon-coated multilayer, and the reflectivity was recovered.
文摘In this paper, the transparent hard diamond-like carbon (DLC) films were deposited on glass substrate by magnetic confined radio-frequency plasma chemical vapor deposition. The structure of films was studied by Raman spectra and X-ray photoelectron spectra (XPS), the transmittance of films by Spectrophotometer. The mechanism of the influence of films structure on transmittance of the films was discussed. The results show that the thickness of films was lower than 100nm, and the transmittance was over 90% in 380-780 nm region. Discussion in theory on the influence of film structure on transmittance was correspondence to experiment results.
基金This work was supported by the Natural Science and Engineering Research Council(NSERC)of Canada.
文摘The production of high quality single-walled carbon nanotubes(SWCNTs)on a bulk scale has been an issue of considerable interest.Recently,it has been demonstrated that high quality SWCNTs can be continuously synthesized on large scale by using induction thermal plasma technology.In this process,the high energy density of the thermal plasma is employed to generate dense vapor-phase precursors for the synthesis of SWCNTs.With the current reactor system,a carbon soot product which contains approximately 40 wt%of SWCNTs can be continuously synthesized at the high production rate of~100 g/h.In this article,our recent research efforts to achieve major advances in this technology are presented.Firstly,the processing parameters involved are examined systematically in order to evaluate their individual inuences on the SWCNT synthesis.Based on these results,the appropriate operating conditions of the induction thermal plasma process for an effective synthesis of SWCNTs are discussed.A characterization study has also been performed on the SWCNTs produced under the optimum processing conditions.Finally,a mathematical model of the process currently under development is described.The model will help us to better understand the synthesis of SWCNTs in the induction plasma process.