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
(-)-Methyl(4R, 5S, 10R)-14-methoxypodocarpa-8, 11, 13-triene-19-oate(1), which is the key intermediate for synthesis of diterpenoids, was synthesized from (R)-(+)-2-methyl-2-(2`-nitrovinyl)-delta-valerolactone(2).
A new sesquiterpene, 12,13-di-acetoxyl-1,4,6,11-eudesmanetetrol 1, was isolated from Michelia yunnanensis. The structure was elucidated on the basis of spectral data.
Three new diterpene alkaloids, transconitine A, B and C were isolated from the roots of Aconitum transsectum Diels, and their structures were elucidated by spectral means.
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(-)-Methyl(4R, 5S, 10R)-14-methoxypodocarpa-8, 11, 13-triene-19-oate(1), which is the key intermediate for synthesis of diterpenoids, was synthesized from (R)-(+)-2-methyl-2-(2`-nitrovinyl)-delta-valerolactone(2).
文摘A new sesquiterpene, 12,13-di-acetoxyl-1,4,6,11-eudesmanetetrol 1, was isolated from Michelia yunnanensis. The structure was elucidated on the basis of spectral data.
文摘Three new diterpene alkaloids, transconitine A, B and C were isolated from the roots of Aconitum transsectum Diels, and their structures were elucidated by spectral means.
