In-situ Mo nanoparticles strengthened CoCrNi medium entropy alloy

In present work, the CoCrNi/Mo mixed powder was designed and fabricated by a novel coating method followed by the calcination and reduction processes. The results indicated that in-situ Mo particles distributed homogeneous among the CoCrNi gas atomized powder and no other drawbacks generated such as contamination and oxidation, the reduced Mo particles were nanoscale, and maximum size did not exceed 600 nm. The SPSed CoCrNi/Mo composite with significant amount of in-situ μ phases showed improved mechanical properties: the yield strength and hardness from 352 MPa to 159 HV to 815 MPa and 375 HV, compared with the pure CoCrNi MEA (medium entropy alloy). The improved properties are mainly attributed to synergistic effects of various strengthening mechanisms, including solid solution strengthening, load transfer effect, Orowan strengthening, grain refinement, especially thermal mismatch mechanism. In addition, this could give insights on the applications of other MEA or HEA-based composites fabricated by coating method.National Natural Science Foundation of Chin

Pulsatilloside C from the roots of Pulsatilla chinensis

A new lupane-type triterpene saponin, pulsatilloside C (1), was isolated from the roots of Pulsatilla chinensis. Its structure was established to be 3 beta,23-dihydroxylup-20(29)-en-28-oic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta- D-glucopyranoside

A New Isoflavone from Smilax glabra

A new isoflavone, 7,6’-dihydroxy-3’-methoxyisoflavone, has been isolated from the roots of Smilax glabra. The structure was determined by 2D-NMR techniques

New lupane glycosides from Pulsatilla chinensis

Two new lupane glycosides along with five known triterpenoids were isolated from the roots of Pulsatilla chinensis (Ranunculaceae). The structures of the new glycosides were determined to be 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-arabinopyranosyl-23-hydroxybetu linic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D- glucopyranosyl ester (pulsatilloside D, 6) and 3-O-[beta-D-glucopyranosyl(1-->4)][alpha-L-rhamnopyranosyl(1-->2)]-a lpha-L-arabinopyranosyl-23-hydroxybetulinic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D- glucopyranosyl ester (pulsatilloside E, 7) by spectroscopic analysis and chemical methods. The compounds were evaluated for cytotoxic activities against K-562 human leukemia and HeLa cells