Differential heats of H 2 adsorption on γNo 2N catalysts were studied by using microcalorimetry.Samples with high and medium surface areas (90 and 17 m2·g -1 ) present a homogeneous energetic distribution of sur...Differential heats of H 2 adsorption on γNo 2N catalysts were studied by using microcalorimetry.Samples with high and medium surface areas (90 and 17 m2·g -1 ) present a homogeneous energetic distribution of surface sites,which corresponds with the preferential orientation of their (200) planes.Molybdenum nitride with low surface area (8 m2·g -1 ) displays a heterogeneous energetic distribution of H 2 adsorption sites.The higher initial differential heat of hydrogen adsorption observed for the low surface Mo nitride was attributed to species adsorbed on surface sites associated with the (111) plane.展开更多
Valence of elements in HgBa_2Ca_(n-1)Cu_nO_(2n+2+δ)(n=1, 2, 3, 4) (both argon and oxygen annealed samples) were calculated. The result indicated for both argon and oxygen annealed samples, Hg had the lowest valence f...Valence of elements in HgBa_2Ca_(n-1)Cu_nO_(2n+2+δ)(n=1, 2, 3, 4) (both argon and oxygen annealed samples) were calculated. The result indicated for both argon and oxygen annealed samples, Hg had the lowest valence for the highest Tc sample. For fixed n, the valence of Cu in oxygen annealed samples was larger than that in argon annealed samples, indicating that oxygen annealed samples produce more carriers than argon annealed samples.展开更多
文摘Differential heats of H 2 adsorption on γNo 2N catalysts were studied by using microcalorimetry.Samples with high and medium surface areas (90 and 17 m2·g -1 ) present a homogeneous energetic distribution of surface sites,which corresponds with the preferential orientation of their (200) planes.Molybdenum nitride with low surface area (8 m2·g -1 ) displays a heterogeneous energetic distribution of H 2 adsorption sites.The higher initial differential heat of hydrogen adsorption observed for the low surface Mo nitride was attributed to species adsorbed on surface sites associated with the (111) plane.
基金National Natural Science Foundation of China !(Grant No. 29871029)Laboratory of Rare Earth Chemistry and Physics, Changchun
文摘Valence of elements in HgBa_2Ca_(n-1)Cu_nO_(2n+2+δ)(n=1, 2, 3, 4) (both argon and oxygen annealed samples) were calculated. The result indicated for both argon and oxygen annealed samples, Hg had the lowest valence for the highest Tc sample. For fixed n, the valence of Cu in oxygen annealed samples was larger than that in argon annealed samples, indicating that oxygen annealed samples produce more carriers than argon annealed samples.
