Semiconductors grown by the solution-processed method have shown low-cost,facile fabrication process and comparable performance.However,there are many reasons why it is difficult to achieve high quality films.For exam...Semiconductors grown by the solution-processed method have shown low-cost,facile fabrication process and comparable performance.However,there are many reasons why it is difficult to achieve high quality films.For example,lattice constant mismatch is one of the problems when photovoltaic devices made of organ metallic perovskites.In this work,MAPbBr^(MA=CH3NH3^+)perovskites single crystals grown on the surface of MAPbBr2.5 CI0.5 perovskites single crystals via liquid epitaxial growth method is demonstrated.It is found that when the lattice constants of the two perovskite single crystals are matched,another crystal can be grown on the surface of one crystal by epitaxial growth.The whole epitaxy growth process does not require high heating temperature and long heating time.X-ray diffraction method is used to prove the lattice plane of the substrate and the epitaxial grown layer.A scanning electron microscope is used to measure the thickness of the epitaxial layer.Compared with perovskite-based photodetectors without epitaxial growth layer,perovskite-based photodetectors with epitaxial growth layer have lower dark current density and higher optical responsibility.展开更多
Blast furnace ironmaking process is the most mature and highly effective process for producing liquid iron.Blast furnace is a gas-solid and gas-solid-liquid countercurrent reactor,and maintaining gas permeability is t...Blast furnace ironmaking process is the most mature and highly effective process for producing liquid iron.Blast furnace is a gas-solid and gas-solid-liquid countercurrent reactor,and maintaining gas permeability is the precondition of smooth production.Therefore,improving the gas permeability throughout the blast furnace remains a hot issue which is concerned by many metallurgical scholars.According to the research results of many scholars,the dominant factors influencing the gas permeability of different locations in the blast furnace(locations are distinguished according to the morphology change of the burdens)were reviewed.And the strategies for improving the gas permeability of different locations in the blast furnace were summarized based on these dominant influencing factors,such as suppressing the low-temperature reduction degradation of sinter in the lump zone,improving the indirect reduction degree and suppressing the interaction between different burdens.It is hoped to provide both theoretical and practical values for guiding the blast furnace so as to improve smooth operation and smelting efficiency.展开更多
The original version of this article unfortunately contained mistakes.Equation(I)and Tables 1 and 2 were incorrect..The corrected equation and tables are given below.
基金the National Key R&D Program of China(Grant Nos.2017YFC0111500 and 2016YFB0401600)the National Natural Science Foundation Project(Grant Nos.61775034,61571124,and 61674029)+1 种基金International Cooperation Program of Jiangsu Province(Grant No.BZ2018056)the NSFC Research Fund for International Young Scientists(Grant No.61750110537).
文摘Semiconductors grown by the solution-processed method have shown low-cost,facile fabrication process and comparable performance.However,there are many reasons why it is difficult to achieve high quality films.For example,lattice constant mismatch is one of the problems when photovoltaic devices made of organ metallic perovskites.In this work,MAPbBr^(MA=CH3NH3^+)perovskites single crystals grown on the surface of MAPbBr2.5 CI0.5 perovskites single crystals via liquid epitaxial growth method is demonstrated.It is found that when the lattice constants of the two perovskite single crystals are matched,another crystal can be grown on the surface of one crystal by epitaxial growth.The whole epitaxy growth process does not require high heating temperature and long heating time.X-ray diffraction method is used to prove the lattice plane of the substrate and the epitaxial grown layer.A scanning electron microscope is used to measure the thickness of the epitaxial layer.Compared with perovskite-based photodetectors without epitaxial growth layer,perovskite-based photodetectors with epitaxial growth layer have lower dark current density and higher optical responsibility.
基金National Key Research and Development Program of China(No.2016YFB0601304).
文摘Blast furnace ironmaking process is the most mature and highly effective process for producing liquid iron.Blast furnace is a gas-solid and gas-solid-liquid countercurrent reactor,and maintaining gas permeability is the precondition of smooth production.Therefore,improving the gas permeability throughout the blast furnace remains a hot issue which is concerned by many metallurgical scholars.According to the research results of many scholars,the dominant factors influencing the gas permeability of different locations in the blast furnace(locations are distinguished according to the morphology change of the burdens)were reviewed.And the strategies for improving the gas permeability of different locations in the blast furnace were summarized based on these dominant influencing factors,such as suppressing the low-temperature reduction degradation of sinter in the lump zone,improving the indirect reduction degree and suppressing the interaction between different burdens.It is hoped to provide both theoretical and practical values for guiding the blast furnace so as to improve smooth operation and smelting efficiency.
文摘The original version of this article unfortunately contained mistakes.Equation(I)and Tables 1 and 2 were incorrect..The corrected equation and tables are given below.
