A Fe-containing mesoporous silica has been synthesized at room temperature using alkylamine as templating surfactant; XRD, IR, ESR and Si-29 MAS NMR spectra provided evidence of the presence of framework and non-frame...A Fe-containing mesoporous silica has been synthesized at room temperature using alkylamine as templating surfactant; XRD, IR, ESR and Si-29 MAS NMR spectra provided evidence of the presence of framework and non-framework iron(III) in Fe-HMS material.展开更多
A novel aluminosilicate with well-defined bimodal mesopore distribution has been synthesized directly, in which one mesopore is distributed at around 3.8nm and the other at 2.6nm.
A mesoporous chromium silicate molecular sieve with MCM-41 structure has beers prepared by direct hydrothermal synthesis; XRD; framework IR, ESR and DR-UV spectroscopies provided evidence of the presence of framework ...A mesoporous chromium silicate molecular sieve with MCM-41 structure has beers prepared by direct hydrothermal synthesis; XRD; framework IR, ESR and DR-UV spectroscopies provided evidence of the presence of framework and extraframework chromium(III) in CrMCM-41 zeolite.展开更多
The effect of prior deformation on the mechanical properties and microstructural evolution of aging process in a Cu-30Ni-25Fe (in at. pct) alloy has been studied by tensile test, hardness measurement, SEM and optical ...The effect of prior deformation on the mechanical properties and microstructural evolution of aging process in a Cu-30Ni-25Fe (in at. pct) alloy has been studied by tensile test, hardness measurement, SEM and optical microscopy analysis. The results show that spinodal decomposition and recovery process interact on each other when aged at low temperature (600 degrees C), and most of the defects induced by cold-work did not disappear in 100 h. When aged at high temperature (850 degrees C), the discontinuous coarsening of the spinodal products takes place. The increase in yield strength and elongation of the sample aged at 850 degrees C for 5 h after deformation mainly results from the submicrometer grains produced by discontinous coarsening of spinodal products.展开更多
We studied the factors affecting the framework aluminium distribution in the ZSM-5 structure by hydrothermal treatment under different conditions. (27)AlMASNMR, XPS and chemical analysis revealed that with steaming at...We studied the factors affecting the framework aluminium distribution in the ZSM-5 structure by hydrothermal treatment under different conditions. (27)AlMASNMR, XPS and chemical analysis revealed that with steaming at lower water vapor pressure, the framework aluminium located at the external surface is less stable. Steaming at higher water vapor pressure is beneficial in removing the framework Al in HZSM-5, and especially helpful in removing that located at the internal surface of HZSM-5. By changing steaming conditions, one may control the framework aluminium distribution in the HZSM-5 structure.展开更多
文摘A Fe-containing mesoporous silica has been synthesized at room temperature using alkylamine as templating surfactant; XRD, IR, ESR and Si-29 MAS NMR spectra provided evidence of the presence of framework and non-framework iron(III) in Fe-HMS material.
文摘A novel aluminosilicate with well-defined bimodal mesopore distribution has been synthesized directly, in which one mesopore is distributed at around 3.8nm and the other at 2.6nm.
文摘A mesoporous chromium silicate molecular sieve with MCM-41 structure has beers prepared by direct hydrothermal synthesis; XRD; framework IR, ESR and DR-UV spectroscopies provided evidence of the presence of framework and extraframework chromium(III) in CrMCM-41 zeolite.
文摘The effect of prior deformation on the mechanical properties and microstructural evolution of aging process in a Cu-30Ni-25Fe (in at. pct) alloy has been studied by tensile test, hardness measurement, SEM and optical microscopy analysis. The results show that spinodal decomposition and recovery process interact on each other when aged at low temperature (600 degrees C), and most of the defects induced by cold-work did not disappear in 100 h. When aged at high temperature (850 degrees C), the discontinuous coarsening of the spinodal products takes place. The increase in yield strength and elongation of the sample aged at 850 degrees C for 5 h after deformation mainly results from the submicrometer grains produced by discontinous coarsening of spinodal products.
文摘We studied the factors affecting the framework aluminium distribution in the ZSM-5 structure by hydrothermal treatment under different conditions. (27)AlMASNMR, XPS and chemical analysis revealed that with steaming at lower water vapor pressure, the framework aluminium located at the external surface is less stable. Steaming at higher water vapor pressure is beneficial in removing the framework Al in HZSM-5, and especially helpful in removing that located at the internal surface of HZSM-5. By changing steaming conditions, one may control the framework aluminium distribution in the HZSM-5 structure.
