Optimized Electronic Bands and Ultralow Lattice Thermal Conductivity in Ag and Y Codoped SnTe.

As a lead-free thermoelectric material, SnTe is inhibited by its inherent high carrier concentration and high thermal conductivity. This work describes the synergistic effect on the modulation of band structure and microstructural defects of SnTe by Ag and Y codoping, which gives rise to band convergence and multiple microstructural defects (secondary phases, dislocations, and boundaries) in the matrix and endows Sn0.94Ag0.09Y0.05Te with an increased power factor of ∼2485 µW m-1 K-2, an extremely low lattice thermal conductivity of ∼0.61 W m-1 K-1, and a peak zT as high as ∼1.2 at 873 K. This work reveals that the combination of Ag and Y could play a role in the synergistic optimization of electronic and phonon transport properties of SnTe by modifying the band structure and microstructures, providing guidance for enhancing the thermoelectric performance of the relevant materials.

[Effect of turmeric volatile oil on proliferation and apoptosis of human skin SCC A431 cells].

To investigate the effect of turmeric volatile oil (TVO) on the apoptosis and proliferation of human skin SCC A431 cells, A431 cells were incubated with different concentrations (5-80 mg•L⁻¹) of TVO in vitro．The proliferation and cell cycle were assessed by CCK8 assay. The change of morphology was observed with inverted microscope. Apoptosis was evaluated with AO/EB double staining and flow cytometry (FCM); cell cycle was analyzed with FCM ．Western blot method was used to detect caspase-3 and caspase-9 protein expression. Results indicated that TVO has significant inhibitory effects on the growth of A431 cells in a dose dependent relationship, the difference between groups has statistically significant (P<0.05). TVO group compared with control group, concentrations in cells shrivel and broken phenomenon, cell apoptosis rate increased, and a dose dependent and increased the expression of caspase-3 and caspase-9. The experiment results suggested that TVO could restrain skin squamous carcinoma A431 cells proliferation, and induce its apoptosis. The mechanism may be related to increase the expression of caspase-3 and caspase-9.