A series of Mn-Mo-W-O_x/TiO_2-SiO_2 catalysts was modified with CeO_2 using an extrusion molding method. The catalytic activities of the obtained catalysts were tested for the synergistic catalytic removals of CO, NO ...A series of Mn-Mo-W-O_x/TiO_2-SiO_2 catalysts was modified with CeO_2 using an extrusion molding method. The catalytic activities of the obtained catalysts were tested for the synergistic catalytic removals of CO, NO and C_3H_8. The ratio of catalyst composition on catalytic activities for NH_3-SCR was optimized, which reveals that the molar ratio of Ti/Si was 9:1 and the catalyst containing 1.5 wt% CeO_2 and 12 wt% Mn-Mo-W-O_x exhibits the best catalytic performances. These samples were characterized by XRD, N_2-BET, Py-IR, NH_3-TPD, SEM/element mapping, H_2-TPR and XPS, respectively. Results show that the optimal catalyst exhibits more than 99% NO conversion, 86% CO conversion and 100% C_3H_8 conversion under GHSV of 5000 h^(-1). In addition, the GHSV has little influence on removal of NO when it is less than 15,000 h^(-1). Furthermore, the addition of CeO_2 will enhance the surface acidity, increase Mn^(4+)concentration and inhibit the grain growth, which are favorable for the excellent catalytic performance.Anyway,the 1.5 wt% CeO_2-12 wt% Mn-Mo-W-O_x/TiO_2-SiO_2 possesses outstanding redox properties,abundant acid sites and high Mn^(4+) concentration, which provide a guarantee for synergistic catalytic removal of CO, NO and HC.展开更多
Vector polarization induced by a change in the scalar phase is far beyond our understanding of the relationship between polarization and phase in classical optics due to the entanglement of the inherent polarized mode...Vector polarization induced by a change in the scalar phase is far beyond our understanding of the relationship between polarization and phase in classical optics due to the entanglement of the inherent polarized modes of light beams.To overcome this limitation,we establish this miraculous relationship by the principle of phase vectorization,which can transform three particular phases into linear,circular and elliptical polarizations.A polarized-spatial light modulator based on the principle of phase vectorization can be achieved using a phase-only spatial light modulator,which not only enables pixel-level polarization manipulation of light beams in a real-time dynamic way but also simultaneously retains complete phase control.This work demonstrates the phase-to-polarization link and reports the creation of a polarized-spatial light modulator,which will transform our view of the natural properties of light beams and pave the way for the era of vector optics.展开更多
基金Project supported by the National Key Research and Development Program of China(2016YFC0205500)National Natural Science Foundation of China(51772149)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘A series of Mn-Mo-W-O_x/TiO_2-SiO_2 catalysts was modified with CeO_2 using an extrusion molding method. The catalytic activities of the obtained catalysts were tested for the synergistic catalytic removals of CO, NO and C_3H_8. The ratio of catalyst composition on catalytic activities for NH_3-SCR was optimized, which reveals that the molar ratio of Ti/Si was 9:1 and the catalyst containing 1.5 wt% CeO_2 and 12 wt% Mn-Mo-W-O_x exhibits the best catalytic performances. These samples were characterized by XRD, N_2-BET, Py-IR, NH_3-TPD, SEM/element mapping, H_2-TPR and XPS, respectively. Results show that the optimal catalyst exhibits more than 99% NO conversion, 86% CO conversion and 100% C_3H_8 conversion under GHSV of 5000 h^(-1). In addition, the GHSV has little influence on removal of NO when it is less than 15,000 h^(-1). Furthermore, the addition of CeO_2 will enhance the surface acidity, increase Mn^(4+)concentration and inhibit the grain growth, which are favorable for the excellent catalytic performance.Anyway,the 1.5 wt% CeO_2-12 wt% Mn-Mo-W-O_x/TiO_2-SiO_2 possesses outstanding redox properties,abundant acid sites and high Mn^(4+) concentration, which provide a guarantee for synergistic catalytic removal of CO, NO and HC.
基金supported by the National Natural Science Foundation of China(62022059/61525503/61620106016/11804232)National key research and development plan“earth observation and navigation”key special project(2017YFB0503102)the National Key Research and Development Program of China(2018YFC1313803).
文摘Vector polarization induced by a change in the scalar phase is far beyond our understanding of the relationship between polarization and phase in classical optics due to the entanglement of the inherent polarized modes of light beams.To overcome this limitation,we establish this miraculous relationship by the principle of phase vectorization,which can transform three particular phases into linear,circular and elliptical polarizations.A polarized-spatial light modulator based on the principle of phase vectorization can be achieved using a phase-only spatial light modulator,which not only enables pixel-level polarization manipulation of light beams in a real-time dynamic way but also simultaneously retains complete phase control.This work demonstrates the phase-to-polarization link and reports the creation of a polarized-spatial light modulator,which will transform our view of the natural properties of light beams and pave the way for the era of vector optics.