All-inorganic CsPbI_3 quantum dots(QDs) have demonstrated promising potential in photovoltaic(PV) applications. However, these colloidal perovskites are vulnerable to the deterioration of surface trap states, leading ...All-inorganic CsPbI_3 quantum dots(QDs) have demonstrated promising potential in photovoltaic(PV) applications. However, these colloidal perovskites are vulnerable to the deterioration of surface trap states, leading to a degradation in efficiency and stability. To address these issues, a facile yet effective strategy of introducing hydroiodic acid(HI) into the synthesis procedure is established to achieve high-quality QDs and devices. Through an in-depth experimental analysis, the introduction of HI was found to convert PbI_2 into highly coordinated [PbI_m]~(2-m), enabling control of the nucleation numbers and growth kinetics. Combined optical and structural investigations illustrate that such a synthesis technique is beneficial for achieving enhanced crystallinity and a reduced density of crystallographic defects. Finally, the effect of HI is further reflected on the PV performance. The optimal device demonstrated a significantly improved power conversion efficiency of 15.72% along with enhanced storage stability. This technique illuminates a novel and simple methodology to regulate the formed species during synthesis, shedding light on ofurther understanding solar cell performance, and aiding the design of future novel synthesis protocols for high-performance optoelectronic devices.展开更多
A compact volume holographic imaging(VHI)method that can detect fluorescence objects located in diffusive medium in spectral selective imaging manner is presented.The enlargement of lateralfield of view of the VHI sys...A compact volume holographic imaging(VHI)method that can detect fluorescence objects located in diffusive medium in spectral selective imaging manner is presented.The enlargement of lateralfield of view of the VHI system is realized by using broadband illumination and demagnification optics.Each target spectrum of°uorescence emitting from a di®usive medium is probed by tuning the inclination angle of the transmission volume holographic grating(VHG).With the use of the single transmission VHG,fluorescence images with different spectrum are obtained sequentially and precise three-dimensional(3D)information of deep fluorescent objects located in a diffusive medium can be reconstructed from these images.The results of phantom experiments demonstrate that two fluorescent objects with a sub-millimeter distance can be resolved by spectral selective imaging.展开更多
1.Background.Polymethyl methacrylate(PMMA)bone cement has been widely used in orthopedic clinics for over 70 years.In 1952 and 1953,Kiaer and Haboush reported their work on the use of PMMA cement to achieve bone adher...1.Background.Polymethyl methacrylate(PMMA)bone cement has been widely used in orthopedic clinics for over 70 years.In 1952 and 1953,Kiaer and Haboush reported their work on the use of PMMA cement to achieve bone adherence to prostheses in femoral head replacement[1,2],.In 1987,Galibert et al.first reported the use of PMMA cement in spinal surgery for vertebroplasty(PVP)to treat vertebral hemangiomas[3].By 2002,approximately 38,000 vertebroplasties and 16,000 kyphoplasties were performed in the United States[4].展开更多
A theoretical framework based on information and embeddedness is constructed to analyze the micro structure of the impact of heterogeneous social capital on corporate performance. It is empirically tested based on dat...A theoretical framework based on information and embeddedness is constructed to analyze the micro structure of the impact of heterogeneous social capital on corporate performance. It is empirically tested based on data collected from a sample of 155 Chinese firms. Results indicate that hierarchical social capital has a positive association with corporate market power but little impact on corporate operational efficiency. Furthermore, social capital can promote operational efficiency but contribute little to corporate market power. There is a complementary structure between the two types of heterogeneous social capital. The embedded inertia of social capital into institutional environment is negatively related with corporate performance. From the perspective of economic transition, firms in developed regions rely far more on hierarchical social capital to acquire market power than firms in developing areas.展开更多
基金financially supported by the National Key Research and Development Program of China (No. 2021YFB3800101 and 2022YFE0110300)National Natural Science Foundation of China (No. U19A2089, 52261145696, 52073198, 92163114, and 22161142003)+3 种基金Natural Science Foundation of Jiangsu Province (BK20211598)“111” projectthe Young Elite Scientist Sponsorship Program by CASTCollaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University。
文摘All-inorganic CsPbI_3 quantum dots(QDs) have demonstrated promising potential in photovoltaic(PV) applications. However, these colloidal perovskites are vulnerable to the deterioration of surface trap states, leading to a degradation in efficiency and stability. To address these issues, a facile yet effective strategy of introducing hydroiodic acid(HI) into the synthesis procedure is established to achieve high-quality QDs and devices. Through an in-depth experimental analysis, the introduction of HI was found to convert PbI_2 into highly coordinated [PbI_m]~(2-m), enabling control of the nucleation numbers and growth kinetics. Combined optical and structural investigations illustrate that such a synthesis technique is beneficial for achieving enhanced crystallinity and a reduced density of crystallographic defects. Finally, the effect of HI is further reflected on the PV performance. The optimal device demonstrated a significantly improved power conversion efficiency of 15.72% along with enhanced storage stability. This technique illuminates a novel and simple methodology to regulate the formed species during synthesis, shedding light on ofurther understanding solar cell performance, and aiding the design of future novel synthesis protocols for high-performance optoelectronic devices.
基金This work is supported by the National Basic Research Program of China(973)under Grant No.2011CB707701the National Natural Science Foundation of China under Grant Nos.61361160418,61322101,81227901,81271617,and 61401246the National Major Scientific Instrument and Equipment Development Project under Grant No.2011YQ030114.
文摘A compact volume holographic imaging(VHI)method that can detect fluorescence objects located in diffusive medium in spectral selective imaging manner is presented.The enlargement of lateralfield of view of the VHI system is realized by using broadband illumination and demagnification optics.Each target spectrum of°uorescence emitting from a di®usive medium is probed by tuning the inclination angle of the transmission volume holographic grating(VHG).With the use of the single transmission VHG,fluorescence images with different spectrum are obtained sequentially and precise three-dimensional(3D)information of deep fluorescent objects located in a diffusive medium can be reconstructed from these images.The results of phantom experiments demonstrate that two fluorescent objects with a sub-millimeter distance can be resolved by spectral selective imaging.
基金supported by the National Natural Science Foundation of China(No.82272165)the Shanghai Committee of Science and Technology(No.20ZR1451800)+1 种基金the Municipal Health Commission Fundation of Shanghai(No.202040141)the Outstanding Youth Foundation Project of Tongren(No.2020SHTRYC02)。
文摘1.Background.Polymethyl methacrylate(PMMA)bone cement has been widely used in orthopedic clinics for over 70 years.In 1952 and 1953,Kiaer and Haboush reported their work on the use of PMMA cement to achieve bone adherence to prostheses in femoral head replacement[1,2],.In 1987,Galibert et al.first reported the use of PMMA cement in spinal surgery for vertebroplasty(PVP)to treat vertebral hemangiomas[3].By 2002,approximately 38,000 vertebroplasties and 16,000 kyphoplasties were performed in the United States[4].
基金This article is sponsored by the Chinese Postdoctoral Science Foundation （No. 200902008）, the Chinese Ministry of Education Humanity and Social Science Foundation （No. 10YJCZH127）, the Chinese Social Science Foundation （No. 11CJY004）, the Faculty Research Fund of Zhongnan University of Economics and Law （No. 31140910513）, and the Central University Young Scholar Research Foundation of Zhongnan University of Economics and Law （No. 2609076）.
文摘A theoretical framework based on information and embeddedness is constructed to analyze the micro structure of the impact of heterogeneous social capital on corporate performance. It is empirically tested based on data collected from a sample of 155 Chinese firms. Results indicate that hierarchical social capital has a positive association with corporate market power but little impact on corporate operational efficiency. Furthermore, social capital can promote operational efficiency but contribute little to corporate market power. There is a complementary structure between the two types of heterogeneous social capital. The embedded inertia of social capital into institutional environment is negatively related with corporate performance. From the perspective of economic transition, firms in developed regions rely far more on hierarchical social capital to acquire market power than firms in developing areas.
