A new technique-series electro-pulse discharg e (SEPD)-was developed as a kind of surface coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes...A new technique-series electro-pulse discharg e (SEPD)-was developed as a kind of surface coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate allo y as an induction electrode. Micro-crystalline Co-Cr and Co-Cr dispersed wit h Y 2O 3 coatings were deposited on Fe-18Cr-8Ni stainless steel surface by using Co30Cr alloy as the depositing electrodes. Oxidation at 950 ℃ in ambie nt air shows that these coatings greatly improve the oxidation resistance of the steel. The addition of dispersed Y 2O 3 nano-particles into the alloy coati ngs was found to further reduce the scaling rate and enhance the adhesion of oxi de scales.展开更多
This study was focused on the influence of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation. A series of CeO2 supports with different contents of active oxygen were obtained by adding surfactant ...This study was focused on the influence of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation. A series of CeO2 supports with different contents of active oxygen were obtained by adding surfactant at different synthesis steps. 0.25 wt% Pt was loaded on these CeO2 supports by incipientwetness impregnation methods. The catalysts were characterized by N2 adsorption, X-ray diffraction（XRD）, high-resolution transmission electron microscopy（HRTEM）, H2 temperature-programmed reduction（H2-TPR）, dynamic oxygen storage capacity（DOSC） and in-situ DRIFTS technologies. For S-f supports, the surfactant was added into the solution before spray-drying in the synthesis process, which facilitates more active oxygen formation on the surface of CeO2. After loading Pt, the more active oxygen on CeO2 contributes to dispersing Pt species and enhancing the CO oxidation activity. As for the aged samples,Pt-R-h shows the highest activity above 190 ℃ because of the presence of more partly oxidized Pt^（δ＋） species. Thus the activity is also influenced by the states of Pt and the Pt^（δ＋） species may contribute to the high activity at elevated temperature.展开更多
文摘A new technique-series electro-pulse discharg e (SEPD)-was developed as a kind of surface coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate allo y as an induction electrode. Micro-crystalline Co-Cr and Co-Cr dispersed wit h Y 2O 3 coatings were deposited on Fe-18Cr-8Ni stainless steel surface by using Co30Cr alloy as the depositing electrodes. Oxidation at 950 ℃ in ambie nt air shows that these coatings greatly improve the oxidation resistance of the steel. The addition of dispersed Y 2O 3 nano-particles into the alloy coati ngs was found to further reduce the scaling rate and enhance the adhesion of oxi de scales.
基金Project supported by the National key research and development program(2016YFC0204901)the National Natural Science Foundation of China(21576207)+1 种基金the Introduction Of Talent and Technology Cooperation Plan Of Tianjin(14RCGFGX00849)GM Global Research&Development(GAC 1539)
文摘This study was focused on the influence of active oxygen on the performance of Pt/CeO2 catalysts for CO oxidation. A series of CeO2 supports with different contents of active oxygen were obtained by adding surfactant at different synthesis steps. 0.25 wt% Pt was loaded on these CeO2 supports by incipientwetness impregnation methods. The catalysts were characterized by N2 adsorption, X-ray diffraction（XRD）, high-resolution transmission electron microscopy（HRTEM）, H2 temperature-programmed reduction（H2-TPR）, dynamic oxygen storage capacity（DOSC） and in-situ DRIFTS technologies. For S-f supports, the surfactant was added into the solution before spray-drying in the synthesis process, which facilitates more active oxygen formation on the surface of CeO2. After loading Pt, the more active oxygen on CeO2 contributes to dispersing Pt species and enhancing the CO oxidation activity. As for the aged samples,Pt-R-h shows the highest activity above 190 ℃ because of the presence of more partly oxidized Pt^（δ＋） species. Thus the activity is also influenced by the states of Pt and the Pt^（δ＋） species may contribute to the high activity at elevated temperature.
