This research is mainly devoted to InSAR observations using Poly-Interferogram Rate and Time-series Estimator (π-rate) software to investigate continuous surface displacement at Mt. Etna (Sicily), Italy between 2003 ...This research is mainly devoted to InSAR observations using Poly-Interferogram Rate and Time-series Estimator (π-rate) software to investigate continuous surface displacement at Mt. Etna (Sicily), Italy between 2003 and 2007. Using ascending and descending SAR images produced by European Space Agency’s ENVISAT, we generate a set of interferograms which are used to determine?the deformation history of Etna from 2003 to 2007. Using (π-rate), we can generate the InSAR?time-series and ratemap while minimizing errors induced by the satellites orbit and atmospheric?phase delays. During the period of 2003-2007, three separate eruptions were observed. In order to explain the deformation, we solve three displacement rate for 2003-2005, 2006 and 2007. As expected, the result suggests that displacement rates are not constant with respect to time. During 2006 the volcano appeared to switch from a period of deflation to a period of inflation. These results highlight the importance of InSAR for generating deformation time-series around Mt.?Etna, and with the application of numerical models these results can be used to estimate the?amount of magma moving in the subsurface.展开更多
A unified linear expression of plastic work rate per unit volume is deduced from the unified linear yield criterion and the associated flow rule. The expression is suitable for various linear yield loci in the error t...A unified linear expression of plastic work rate per unit volume is deduced from the unified linear yield criterion and the associated flow rule. The expression is suitable for various linear yield loci in the error triangle between Tresca’s and twin shear stress yield loci on the π-plane. It exhibits generalization in which the different value of criterion parameter b corresponds to a specific linear formula of plastic work rate per unit volume. Finally, with the unified linear expression of plastic work rate and upper-bound parallel velocity field the strip forging without bulge is successfully analyzed and an analytical result is also obtained. The comparison with traditional solutions shows that when b=1/(1+ 3 ) the result is the same as the upper bound result by Mises’ yield criterion, and it also is identical to that by slab method with m=1, σ0=0.展开更多
Tin-based perovskite solar cells(TPSCs)as the most promising candidate for lead-free PSCs have incurred extensive researches all over the world.However,the crystallization process of tin-based perovskite is too fast d...Tin-based perovskite solar cells(TPSCs)as the most promising candidate for lead-free PSCs have incurred extensive researches all over the world.However,the crystallization process of tin-based perovskite is too fast during the solution-deposited process,resulting in abundant pinholes and poor homogeneity that cause serious charge recombination in perovskite layer.Here,we employed theπ-conjugated Lewis base molecules with high electron density to systematically control the crystallization rate of FASnI3 perovskite by forming stable intermediate phase with the Sn-I frameworks,leading to a compact and uniform perovskite film with large increase in the carrier lifetime.Meanwhile,the introduction of theπ-conjugated systems also retards the permeation of moisture into perovskite crystal,which significantly suppresses the film degradation in air.These benefits contributed to a stabilizing power conversion efficiency(PCE)of 10.1%for the TPSCs and maintained over 90%of its initial PCE after 1000-h light soaking in air.Also,a steady-state efficiency of 9.2%was certified at the accredited test center.展开更多
文摘This research is mainly devoted to InSAR observations using Poly-Interferogram Rate and Time-series Estimator (π-rate) software to investigate continuous surface displacement at Mt. Etna (Sicily), Italy between 2003 and 2007. Using ascending and descending SAR images produced by European Space Agency’s ENVISAT, we generate a set of interferograms which are used to determine?the deformation history of Etna from 2003 to 2007. Using (π-rate), we can generate the InSAR?time-series and ratemap while minimizing errors induced by the satellites orbit and atmospheric?phase delays. During the period of 2003-2007, three separate eruptions were observed. In order to explain the deformation, we solve three displacement rate for 2003-2005, 2006 and 2007. As expected, the result suggests that displacement rates are not constant with respect to time. During 2006 the volcano appeared to switch from a period of deflation to a period of inflation. These results highlight the importance of InSAR for generating deformation time-series around Mt.?Etna, and with the application of numerical models these results can be used to estimate the?amount of magma moving in the subsurface.
基金Project(50474015) supported by the National Natural Science Foundation of ChinaProject(RAL–SD-2008-2) supported by RAL Self-determination Science Foundation
文摘A unified linear expression of plastic work rate per unit volume is deduced from the unified linear yield criterion and the associated flow rule. The expression is suitable for various linear yield loci in the error triangle between Tresca’s and twin shear stress yield loci on the π-plane. It exhibits generalization in which the different value of criterion parameter b corresponds to a specific linear formula of plastic work rate per unit volume. Finally, with the unified linear expression of plastic work rate and upper-bound parallel velocity field the strip forging without bulge is successfully analyzed and an analytical result is also obtained. The comparison with traditional solutions shows that when b=1/(1+ 3 ) the result is the same as the upper bound result by Mises’ yield criterion, and it also is identical to that by slab method with m=1, σ0=0.
基金supported by the National Natural Science Foundation of China(11574199,11674219,11834011)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning+1 种基金National Institute for Materials Science was supported by the New Energy and Industrial Technology Development Organization(NEDO,Japan)the KAKEHI Grant of Japan(18H02078)
文摘Tin-based perovskite solar cells(TPSCs)as the most promising candidate for lead-free PSCs have incurred extensive researches all over the world.However,the crystallization process of tin-based perovskite is too fast during the solution-deposited process,resulting in abundant pinholes and poor homogeneity that cause serious charge recombination in perovskite layer.Here,we employed theπ-conjugated Lewis base molecules with high electron density to systematically control the crystallization rate of FASnI3 perovskite by forming stable intermediate phase with the Sn-I frameworks,leading to a compact and uniform perovskite film with large increase in the carrier lifetime.Meanwhile,the introduction of theπ-conjugated systems also retards the permeation of moisture into perovskite crystal,which significantly suppresses the film degradation in air.These benefits contributed to a stabilizing power conversion efficiency(PCE)of 10.1%for the TPSCs and maintained over 90%of its initial PCE after 1000-h light soaking in air.Also,a steady-state efficiency of 9.2%was certified at the accredited test center.