Evaporation of sessile water droplet on polydimethylsiloxane （PDMS） surfaces with three different curing ratios （5：1, 10：1, and 20：1） was experimentally investigated in this paper. We show that the constant con...Evaporation of sessile water droplet on polydimethylsiloxane （PDMS） surfaces with three different curing ratios （5：1, 10：1, and 20：1） was experimentally investigated in this paper. We show that the constant contact radius （CCR） evaporation on surface with high curing ratio lasts longer than that with low curing ratio. We also measured Young＇s moduli of PDMS films by using atomic force microscopy （AFM） and simulated surface deformation of PDMS films induced by sessile water droplet. With increasing curing ratio of PDMS film, Young＇s modulus of PDMS film is getting lower, and then there will be larger surface deformation and more elastic stored energy. Since such energy acts as a barrier to keep the three-phase contact line pinned, thus it will result in longer CCR evaporation on PDMS surface with higher curing ratio.展开更多
In the present work, we analyse the delamination problem under the combined dynamic load. We show the effect of background harmonic vibrations on critical amplitudes of the principal force pulse. The effect is demonst...In the present work, we analyse the delamination problem under the combined dynamic load. We show the effect of background harmonic vibrations on critical amplitudes of the principal force pulse. The effect is demonstrated on the simple model of a string on an elastic foundation and the fracture phenomenon is predicted by the incubation time criterion. The results state the possibility of considerable decrease in threshold amplitude by a proper choice of the frequency of a background excitation.展开更多
基金supported by the National Natural Science Foundation of China(11002051,11072244,and 11372313)the Key Research Program of the Chinese Academy of Sciences(KJZDEW-M01)the Instrument Developing Project of the Chinese Academy of Sciences(Y2010031)
文摘Evaporation of sessile water droplet on polydimethylsiloxane （PDMS） surfaces with three different curing ratios （5：1, 10：1, and 20：1） was experimentally investigated in this paper. We show that the constant contact radius （CCR） evaporation on surface with high curing ratio lasts longer than that with low curing ratio. We also measured Young＇s moduli of PDMS films by using atomic force microscopy （AFM） and simulated surface deformation of PDMS films induced by sessile water droplet. With increasing curing ratio of PDMS film, Young＇s modulus of PDMS film is getting lower, and then there will be larger surface deformation and more elastic stored energy. Since such energy acts as a barrier to keep the three-phase contact line pinned, thus it will result in longer CCR evaporation on PDMS surface with higher curing ratio.
基金supported by the Russian Foundation for Basic Research(16-51-53077)the National Natural Science Foundation of China(11611130019)
文摘In the present work, we analyse the delamination problem under the combined dynamic load. We show the effect of background harmonic vibrations on critical amplitudes of the principal force pulse. The effect is demonstrated on the simple model of a string on an elastic foundation and the fracture phenomenon is predicted by the incubation time criterion. The results state the possibility of considerable decrease in threshold amplitude by a proper choice of the frequency of a background excitation.
