We explore the photoluminescence properties of zinc silicate(Zn_(2)SiO_(4)) nanostructures synthesized by vapor-liquidsolid(VLS)mode of growth using three different catalysts(Sn,Ag,and Mn).Different catalysts signific...We explore the photoluminescence properties of zinc silicate(Zn_(2)SiO_(4)) nanostructures synthesized by vapor-liquidsolid(VLS)mode of growth using three different catalysts(Sn,Ag,and Mn).Different catalysts significantly influence the growth rate which in turn has an impact on the structure and hence the photoluminescence of the prepared zinc silicate nanostructures.Zn_(2)SiO_(4) has a wide bandgap of about 5.5 eV and in its pure form,it does not emit in visible region due to its inner shell electronic transitions between the 3 d5 energy levels.However,the incorporation of different catalysts(Sn,Ag and Mn)at different growth temperatures into the Zn_(2)SiO_(4) crystal growth kinetics provides wide visible spectral range of photoluminescence(PL)emissions.PL analysis shows broad multi-band spectrum in the visible region and distinct colors(red,yellow,green,blue,cyan and violet)are obtained depending on the crystalline structure of the prepared nanostructures.The allowed transitions due to the effect of different catalysts on zinc silicate lattice offer a huge cross-section of absorption that generates strong photoluminescence.The correlation between the structural and optical properties of the synthesized nanostructures is discussed in detail.The synthesized photoluminescent nanostructures have potential applications in solidstate lighting and display devices.展开更多
Transition metal oxides have attracted intense interest owing to their abundant physical and chemical properties.The controlled preparation of large-area,high-quality two-dimensional crystals is essential for revealin...Transition metal oxides have attracted intense interest owing to their abundant physical and chemical properties.The controlled preparation of large-area,high-quality two-dimensional crystals is essential for revealing their inherent properties and realizing high-performance devices.However,fabricating two-dimensional(2D)transition metal oxides using a general approach still presents substantial challenges.Herein,we successfully achieve highly crystalline nickel oxide(NiO)flakes with a thickness as thin as 3.3 nm through the salt-assisted vapor-liquid-solid(VLS)growth method,which demonstrated exceptional stability under ambient conditions.To explore the great potential of the NiO crystal in this work,an artificial synapse based on the NiO-flake resistive switching(RS)layer is investigated.Short-term and long-term synaptic behaviors are obtained with external stimuli.The artificial synaptic performance provides the foundation of the neuromorphic application,including handwriting number recognition based on artificial neuron network(ANN)and the virtually unsupervised learning capability based on generative adversarial network(GAN).This pioneering work not only paves new paths for the synthesis of 2D oxides in the future but also demonstrates the substantial potential of oxides in the field of neuromorphic computing.展开更多
Preliminary experimental studies on evaporation of Gengnian’an liquid extract of traditional Chinese medicine(TCM)with vapor-liquid-solid flow boiling technique were carried out in a transparent natual circulating th...Preliminary experimental studies on evaporation of Gengnian’an liquid extract of traditional Chinese medicine(TCM)with vapor-liquid-solid flow boiling technique were carried out in a transparent natual circulating three-phase evaporator. The height of the heating tube is 2.5 m with an inner diameter of 0.038 m and an outer diameter of 0.045 m. The cylindrical solid particles with a diameter of 0.0025 m and a length of 0.0025 m is made of a kind of inert material that does not interact with the liquid of Gengnian’an. The heat energy for the evaporator was supplied by the electric heating system. It was shown that the presence of the solid particles could enhance the process of heat transfer since the heat transfer coefficients in vapor-liquid-solid boiling system was about 1.5-2.0 times that of the vapor-liquid boiling system when the heat flux was constant. On the other hand,fouling prevention and a lower wall temperature were also seen when the solid particles were present. The quality of concentrated liquid of TCM would be improved.展开更多
文摘We explore the photoluminescence properties of zinc silicate(Zn_(2)SiO_(4)) nanostructures synthesized by vapor-liquidsolid(VLS)mode of growth using three different catalysts(Sn,Ag,and Mn).Different catalysts significantly influence the growth rate which in turn has an impact on the structure and hence the photoluminescence of the prepared zinc silicate nanostructures.Zn_(2)SiO_(4) has a wide bandgap of about 5.5 eV and in its pure form,it does not emit in visible region due to its inner shell electronic transitions between the 3 d5 energy levels.However,the incorporation of different catalysts(Sn,Ag and Mn)at different growth temperatures into the Zn_(2)SiO_(4) crystal growth kinetics provides wide visible spectral range of photoluminescence(PL)emissions.PL analysis shows broad multi-band spectrum in the visible region and distinct colors(red,yellow,green,blue,cyan and violet)are obtained depending on the crystalline structure of the prepared nanostructures.The allowed transitions due to the effect of different catalysts on zinc silicate lattice offer a huge cross-section of absorption that generates strong photoluminescence.The correlation between the structural and optical properties of the synthesized nanostructures is discussed in detail.The synthesized photoluminescent nanostructures have potential applications in solidstate lighting and display devices.
基金support from the Jiangsu Funding Program for Excellent Postdoctoral Talent,the National Natural Science Foundation of China(No.52372055)the Jiangsu Independent Innovation Fund Project of Agricultural Science and Technology(No.CX(21)3163).
文摘Transition metal oxides have attracted intense interest owing to their abundant physical and chemical properties.The controlled preparation of large-area,high-quality two-dimensional crystals is essential for revealing their inherent properties and realizing high-performance devices.However,fabricating two-dimensional(2D)transition metal oxides using a general approach still presents substantial challenges.Herein,we successfully achieve highly crystalline nickel oxide(NiO)flakes with a thickness as thin as 3.3 nm through the salt-assisted vapor-liquid-solid(VLS)growth method,which demonstrated exceptional stability under ambient conditions.To explore the great potential of the NiO crystal in this work,an artificial synapse based on the NiO-flake resistive switching(RS)layer is investigated.Short-term and long-term synaptic behaviors are obtained with external stimuli.The artificial synaptic performance provides the foundation of the neuromorphic application,including handwriting number recognition based on artificial neuron network(ANN)and the virtually unsupervised learning capability based on generative adversarial network(GAN).This pioneering work not only paves new paths for the synthesis of 2D oxides in the future but also demonstrates the substantial potential of oxides in the field of neuromorphic computing.
基金国家青年科学基金 (No 2 0 10 60 12 )天津市科委中药现代化专项基金 (No 0 13 10 86112 )+1 种基金天津市131人才引进基金天津大学青年教师科研启动基金~~
文摘Preliminary experimental studies on evaporation of Gengnian’an liquid extract of traditional Chinese medicine(TCM)with vapor-liquid-solid flow boiling technique were carried out in a transparent natual circulating three-phase evaporator. The height of the heating tube is 2.5 m with an inner diameter of 0.038 m and an outer diameter of 0.045 m. The cylindrical solid particles with a diameter of 0.0025 m and a length of 0.0025 m is made of a kind of inert material that does not interact with the liquid of Gengnian’an. The heat energy for the evaporator was supplied by the electric heating system. It was shown that the presence of the solid particles could enhance the process of heat transfer since the heat transfer coefficients in vapor-liquid-solid boiling system was about 1.5-2.0 times that of the vapor-liquid boiling system when the heat flux was constant. On the other hand,fouling prevention and a lower wall temperature were also seen when the solid particles were present. The quality of concentrated liquid of TCM would be improved.
