Palladium(Pd)-based sulfides have triggered extensive interest due to their unique properties and potential applications in the fields of electronics and optoelectronics.However,the synthesis of large-scale uniform Pd...Palladium(Pd)-based sulfides have triggered extensive interest due to their unique properties and potential applications in the fields of electronics and optoelectronics.However,the synthesis of large-scale uniform PdS and PdS_(2)nanofilms(NFs)remains an enormous challenge.In this work,2-inch wafer-scale PdS and PdS_(2) NFs with excellent stability can be controllably prepared via chemical vapor deposition combined with electron beam evaporation technique.The thickness of the pre-deposited Pd film and the sulfurization temperature are critical for the precise synthesis of PdS and PdS_(2) NFs.A corresponding growth mechanism has been proposed based on our experimental results and Gibbs free energy calculations.The electrical transport properties of PdS and PdS_(2) NFs were explored by conductive atomic force microscopy.Our findings have achieved the controllable growth of PdS and PdS_(2) NFs,which may provide a pathway to facilitate PdS and PdS_(2) based applications for next-generation high performance optoelectronic devices.展开更多
To evaluate the importance of the canyon topography effects on large structures, based on a rigid frame bridge across a 137-m-deep and 600-m-wide canyon, the seismic response of the canyon site is analyzed using a two...To evaluate the importance of the canyon topography effects on large structures, based on a rigid frame bridge across a 137-m-deep and 600-m-wide canyon, the seismic response of the canyon site is analyzed using a two-dimensional finite element model under different seismic SV waves with the assumptions of vertical incidence and oblique incidence to obtain the ground motions, which are used as the excitation input on the pier foundations of the bridge with improved large mass method. The results indicate that canyon topography has significant influences on the ground motions in terms of incident angle. The peak ground acceleration values vary greatly from the bottom of the canyon to the upper corners. Under vertical incident SV waves, at the upper corners of canyon the peak ground accelerations greatly increase; whereas the peak ground accelerations diminish at the bottom corners of canyon. Under oblique incident SV waves, the shaking of the canyon slope perpendicular to the incidence direction is much more severe than that of the opposite side of canyon. And the ground surface has been characterized by larger deformations in the case of oblique incident waves. It is also concluded that the low piers and frame of the continuous rigid frame bridge are more sensitive to the multi-support seismic excitations than the flexible high piers. The canyon topography as well as the oblique incidence of the waves brings the continuous rigid frame bridge severe responses, which should be taken into account in bridge design.展开更多
p-Terphenyls are aromatic compounds consisting of a central benzene ring substituted with two phenyl groups,and they are mainly isolated from terrestrial and marine organisms.The central ring of p-Terphenyls is usuall...p-Terphenyls are aromatic compounds consisting of a central benzene ring substituted with two phenyl groups,and they are mainly isolated from terrestrial and marine organisms.The central ring of p-Terphenyls is usually modified into more oxidized forms,e.g.,para quinone and phenols.In some cases,additional ring systems were observed on the terphenyl-type core structure or between two benzene moieties.p-Terphenyls have been reported to have cytotoxic,antimicrobial,antioxidant andα-glucosidase inhibitory effects.In this review,we will mainly summarize the structural diversity and biological activity of naturally occurring p-Terphenyls referring to the research works published before.展开更多
基金supported by National Natural Science Foundation of China (No.11974301)Key Research and Development Program of Hunan Province (No.2022GK2007)+2 种基金Key Project from Department Education of Hunan Province (No.22A0123)Scientific Research Fund of Hunan Provincial Education Department (No.21B0136)National college students innovation and entrepreneurship training program (No.S202310530016)。
文摘Palladium(Pd)-based sulfides have triggered extensive interest due to their unique properties and potential applications in the fields of electronics and optoelectronics.However,the synthesis of large-scale uniform PdS and PdS_(2)nanofilms(NFs)remains an enormous challenge.In this work,2-inch wafer-scale PdS and PdS_(2) NFs with excellent stability can be controllably prepared via chemical vapor deposition combined with electron beam evaporation technique.The thickness of the pre-deposited Pd film and the sulfurization temperature are critical for the precise synthesis of PdS and PdS_(2) NFs.A corresponding growth mechanism has been proposed based on our experimental results and Gibbs free energy calculations.The electrical transport properties of PdS and PdS_(2) NFs were explored by conductive atomic force microscopy.Our findings have achieved the controllable growth of PdS and PdS_(2) NFs,which may provide a pathway to facilitate PdS and PdS_(2) based applications for next-generation high performance optoelectronic devices.
基金supported by National Natural Science Foundation of China (No. 50708100)National Science and Technology Support Project of China (No. 2006BAC13B02)partially by Basic Research Program of Institute of Mechanics Engineering, China Earthquake Administration (No. 2007B02)
文摘To evaluate the importance of the canyon topography effects on large structures, based on a rigid frame bridge across a 137-m-deep and 600-m-wide canyon, the seismic response of the canyon site is analyzed using a two-dimensional finite element model under different seismic SV waves with the assumptions of vertical incidence and oblique incidence to obtain the ground motions, which are used as the excitation input on the pier foundations of the bridge with improved large mass method. The results indicate that canyon topography has significant influences on the ground motions in terms of incident angle. The peak ground acceleration values vary greatly from the bottom of the canyon to the upper corners. Under vertical incident SV waves, at the upper corners of canyon the peak ground accelerations greatly increase; whereas the peak ground accelerations diminish at the bottom corners of canyon. Under oblique incident SV waves, the shaking of the canyon slope perpendicular to the incidence direction is much more severe than that of the opposite side of canyon. And the ground surface has been characterized by larger deformations in the case of oblique incident waves. It is also concluded that the low piers and frame of the continuous rigid frame bridge are more sensitive to the multi-support seismic excitations than the flexible high piers. The canyon topography as well as the oblique incidence of the waves brings the continuous rigid frame bridge severe responses, which should be taken into account in bridge design.
基金supported by the NSFC-Shandong Joint Fund(U1906212,U1606403)the Pilot National Laboratory for Marine Science and Technology(2018SDKJ0401-2,2016ASKJ08-02)+5 种基金the National Natural Science Foundation of China Major Project for Discovery of New Leading Compounds(81991522)the National Science and Technology Major Project for Significant New Drugs Development(2018ZX09735004)the Major National Science and Technology Projects of the Ministry of Science and Technology(81991522)the Fundamental Research Funds for the Central Universities(201941001)Project funded by China Postdoctoral Science Foundation(2017M622286)the Taishan Scholar Youth Expert Program in Shandong Province(tsqn201812021).
文摘p-Terphenyls are aromatic compounds consisting of a central benzene ring substituted with two phenyl groups,and they are mainly isolated from terrestrial and marine organisms.The central ring of p-Terphenyls is usually modified into more oxidized forms,e.g.,para quinone and phenols.In some cases,additional ring systems were observed on the terphenyl-type core structure or between two benzene moieties.p-Terphenyls have been reported to have cytotoxic,antimicrobial,antioxidant andα-glucosidase inhibitory effects.In this review,we will mainly summarize the structural diversity and biological activity of naturally occurring p-Terphenyls referring to the research works published before.
