We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and...We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and possesses different transmission conditions.Using the variational method,we obtain the well posedness of the interior transmission problem,which plays an important role in the proof of the discreteness of eigenvalues.Then we achieve the existence of an infinite discrete set of transmission eigenvalues provided that n≡1,where a fourth order differential operator is applied.In the case of n■1,we show the discreteness of the transmission eigenvalues under restrictive assumptions by the analytic Fredholm theory and the T-coercive method.展开更多
In-depth understandings of charge carrier transfer dynamics in any artificial catalytic system are of critical importance for the future design of highly efficient photocatalysts.Herein,we synthesized sub-monolayer Zn...In-depth understandings of charge carrier transfer dynamics in any artificial catalytic system are of critical importance for the future design of highly efficient photocatalysts.Herein,we synthesized sub-monolayer ZnSe partial-shell coated CdSe/CdS core/shell quantum dots in a controlled fashion.The ZnSe decorated quantum dots were employed as a model catalyst for photogeneration of H_(2)under light illumination.Both theoretical calculations and experimental results unravel that the growth of ZnSe partial-shell would retard the photogenerated electron transfer,and meanwhile,accelerate the corresponding hole migration process during the H_(2)photogeneration reaction in the artificial photocatalytic system.As such,the performance of the relevant photocatalytic system can be modulated and optimized,and accordingly,a plausible underlying mechanism is rationalized.展开更多
To achieve radar and infrared stealth, an infrared stealth layer is usually added to the radar absorbing material（RAM） of stealth aircraft. By analyzing the millimeter-wave（MMW） emissivities of three stealth mater...To achieve radar and infrared stealth, an infrared stealth layer is usually added to the radar absorbing material（RAM） of stealth aircraft. By analyzing the millimeter-wave（MMW） emissivities of three stealth materials, this Letter investigates the impact of the added infrared stealth layer on the originally ＂hot＂ MMW emission of RAM. The theoretical and measured results indicate that, compared with the monolayer RAM, the MMW emission of the bilayer material is still strong and its emissivity is reduced by 0.1–0.2 at almost every incident angle.The results partially demonstrate the feasibility of detecting stealth aircraft coated with this bilayer stealth material.展开更多
基金supported by the National Natural Science Foundation of China(11571132,12301542)the Natural Science Foundation of Hubei(2022CFB725)the Natural Science Foundation of Yichang(A23-2-027)。
文摘We consider the interior transmission eigenvalue problem corresponding to the scattering for an anisotropic medium of the scalar Helmholtz equation in the case where the boundary?Ωis split into two disjoint parts and possesses different transmission conditions.Using the variational method,we obtain the well posedness of the interior transmission problem,which plays an important role in the proof of the discreteness of eigenvalues.Then we achieve the existence of an infinite discrete set of transmission eigenvalues provided that n≡1,where a fourth order differential operator is applied.In the case of n■1,we show the discreteness of the transmission eigenvalues under restrictive assumptions by the analytic Fredholm theory and the T-coercive method.
文摘In-depth understandings of charge carrier transfer dynamics in any artificial catalytic system are of critical importance for the future design of highly efficient photocatalysts.Herein,we synthesized sub-monolayer ZnSe partial-shell coated CdSe/CdS core/shell quantum dots in a controlled fashion.The ZnSe decorated quantum dots were employed as a model catalyst for photogeneration of H_(2)under light illumination.Both theoretical calculations and experimental results unravel that the growth of ZnSe partial-shell would retard the photogenerated electron transfer,and meanwhile,accelerate the corresponding hole migration process during the H_(2)photogeneration reaction in the artificial photocatalytic system.As such,the performance of the relevant photocatalytic system can be modulated and optimized,and accordingly,a plausible underlying mechanism is rationalized.
基金supported partially by the Shanghai Spaceflight Technology Renovation Fund(No.SAST2015088)the Fundamental Research Fund for the Central Universities(No.HUST2015QN093)
文摘To achieve radar and infrared stealth, an infrared stealth layer is usually added to the radar absorbing material（RAM） of stealth aircraft. By analyzing the millimeter-wave（MMW） emissivities of three stealth materials, this Letter investigates the impact of the added infrared stealth layer on the originally ＂hot＂ MMW emission of RAM. The theoretical and measured results indicate that, compared with the monolayer RAM, the MMW emission of the bilayer material is still strong and its emissivity is reduced by 0.1–0.2 at almost every incident angle.The results partially demonstrate the feasibility of detecting stealth aircraft coated with this bilayer stealth material.
