The optical microcavity effect of the homo-tandem solar cells is explored utilizing the transfer matrix method.Ultrathin silver can reduce the deadzone effect compared with graphene and PH1000, and leads to a factor o...The optical microcavity effect of the homo-tandem solar cells is explored utilizing the transfer matrix method.Ultrathin silver can reduce the deadzone effect compared with graphene and PH1000, and leads to a factor of1.07 enhancement for an electrical field in a metal microcavity. The enhancement is considered to be the fact that strong exciton-photon coupling occurs in the microcavity due to ultrathin Ag. On the basis of the optical enhancement effect, optical behaviors are manipulated by varying the microcavity length. It is confirmed that ultrathin silver can serve as an ideal interconnection layer as the active layer is^150 nm thick and the thickness ratio between front and rear active layers lies between 1:1 and 1:2.展开更多
The effect of adding Ta on the changes of microstructure and Ms temperature of a dualphase shape memory alloy with compositions of (Ni51 Ti49)1 -x.Tax. and Ni50-Ti50 -g.Ta.g were systematically studied. An optical mic...The effect of adding Ta on the changes of microstructure and Ms temperature of a dualphase shape memory alloy with compositions of (Ni51 Ti49)1 -x.Tax. and Ni50-Ti50 -g.Ta.g were systematically studied. An optical microscope, SEM, X-ray diffraction and DSC were utilized in this work. The evolution of the microstructure as a function of Ta content was characterized. The variation of the Ni/Ti ratio in the NiTi phase plays an important role in the change of the Ms temperatures due to the addition of Ta. A pseudobinary NiTi-Ta phase diagram was proposed based on these results.展开更多
Rock behavior is usually run into in study on geological deformation, teetono-mineralization and civil engineering.Rock behavior contains its texture,structure and composition,rock property,and its occurrence backgrou...Rock behavior is usually run into in study on geological deformation, teetono-mineralization and civil engineering.Rock behavior contains its texture,structure and composition,rock property,and its occurrence background or situation. That is to say, temperature, compression,content of water and other liquid in rocks, boundary condition of rock block,straining rate etc.,which are closely related to the depth of occurrence of rock, influence on the rock behavior and deformation effects.展开更多
Currently the catalysis of hydrogen evolution reaction(HER)is mainly focused on the inherent electrocatalytic activity at relatively lower current densities while scarce at high current densities.Nevertheless,the latt...Currently the catalysis of hydrogen evolution reaction(HER)is mainly focused on the inherent electrocatalytic activity at relatively lower current densities while scarce at high current densities.Nevertheless,the latter is highly demanding in efficient mass-production of hydrogen.A SiO_(2) nanospheres template-synthesis is used to prepare mesoporous molybdenum carbide nanocrystals-embedded nitrogen-doped carbon foams(mp-Mo_(2)C/NC).The material shows much more excellent catalytic activity than the non-etched Mo_(2)C/NC toward hydrogen evolution reaction(HER)in acidic medium.More interestingly mp-Mo_(2)C/NC still has larger overpotential than Pt/C at lower current densities,but possess remarkably smaller overpotential than the latter at higher current densities for much better electrocatalytic performance.An approach is developed to investigate the electrode kinetics by Tafel plots,especially with eliminating the diffusion effect,indicating that Pt/C and mp-Mo_(2)C/NC display different reaction mechanisms.At low current densities the former presents reversible reaction,while the latter shows mixed electrochemical polarization/reversible electrode process.In the region of higher current densities,the former becomes totally gas-diffusion controlled with large overpotential,while the latter can still retain an electrode polarization process for much lower overpotential at the same current density.Result endorses that the meso-porously structured mp-Mo_(2)C/NC plays a critical role in avoiding gas diffusion control-resulting large overpotential at high current densities.This work holds great potential for an inexpensive catalyst better than Pt/C in practical applications of mass-production hydrogen at high current densities,while clearly shedding fundamental lights on designs of rational HER catalysts for the uses at high current densities.展开更多
As one of the indispensable actuating components in micro-systems,the shafted microgear is in great production demand.Microforming is a manufacturing process to produce microgears to meet the needs.Due to the small ge...As one of the indispensable actuating components in micro-systems,the shafted microgear is in great production demand.Microforming is a manufacturing process to produce microgears to meet the needs.Due to the small geometrical size,there are uncertain process performance and product quality issues in this production process.In this study,the shafted microgears were fabricated in two different scaling factors with four grain sizes using a progressively extrusion-blanking method.To explore the unknown of the process,grain-based modeling was proposed and employed to simulate the entire forming process.The results show that when the grains are large,the anisotropy of single grains has an obvious size effect on the forming behavior and process performance;and the produced geometries and surface quality are worsened;and the deformation load is decreased.Five deformation zones were identified in the microstructures with different hardness and distributions of stress and strain.The simulation by using the proposed model successfully predicted the formation of zones and revealed the inhomogeneous deformation in the forming process.The undesirable geometries of microgears including material unfilling,burr and inclination were observed on the shaft and teeth of gear,and the inclination size is increased obviously with grain size.To avoid the formation of inclination and material unfilling,the punch was redesigned,and a die insert was added to constraint the bottom surface of the gear teeth.The new products had then the better forming quality.展开更多
The purpose of this paper is to study the long time asymptotic behavior for anonlinear Schrdinger equations with magnetic effect. Under certain conditions, we prove theexistence and nonexistence of the non-trivial fre...The purpose of this paper is to study the long time asymptotic behavior for anonlinear Schrdinger equations with magnetic effect. Under certain conditions, we prove theexistence and nonexistence of the non-trivial free asymptotic solutions. In addition, the decayestimates of the solutions are also obtained.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61565015the Western Light Talent Training Program of Chinese Academy of Sciences
文摘The optical microcavity effect of the homo-tandem solar cells is explored utilizing the transfer matrix method.Ultrathin silver can reduce the deadzone effect compared with graphene and PH1000, and leads to a factor of1.07 enhancement for an electrical field in a metal microcavity. The enhancement is considered to be the fact that strong exciton-photon coupling occurs in the microcavity due to ultrathin Ag. On the basis of the optical enhancement effect, optical behaviors are manipulated by varying the microcavity length. It is confirmed that ultrathin silver can serve as an ideal interconnection layer as the active layer is^150 nm thick and the thickness ratio between front and rear active layers lies between 1:1 and 1:2.
文摘The effect of adding Ta on the changes of microstructure and Ms temperature of a dualphase shape memory alloy with compositions of (Ni51 Ti49)1 -x.Tax. and Ni50-Ti50 -g.Ta.g were systematically studied. An optical microscope, SEM, X-ray diffraction and DSC were utilized in this work. The evolution of the microstructure as a function of Ta content was characterized. The variation of the Ni/Ti ratio in the NiTi phase plays an important role in the change of the Ms temperatures due to the addition of Ta. A pseudobinary NiTi-Ta phase diagram was proposed based on these results.
文摘Rock behavior is usually run into in study on geological deformation, teetono-mineralization and civil engineering.Rock behavior contains its texture,structure and composition,rock property,and its occurrence background or situation. That is to say, temperature, compression,content of water and other liquid in rocks, boundary condition of rock block,straining rate etc.,which are closely related to the depth of occurrence of rock, influence on the rock behavior and deformation effects.
基金supported by the Start-up grant from Suzhou University of Science and Technology.
文摘Currently the catalysis of hydrogen evolution reaction(HER)is mainly focused on the inherent electrocatalytic activity at relatively lower current densities while scarce at high current densities.Nevertheless,the latter is highly demanding in efficient mass-production of hydrogen.A SiO_(2) nanospheres template-synthesis is used to prepare mesoporous molybdenum carbide nanocrystals-embedded nitrogen-doped carbon foams(mp-Mo_(2)C/NC).The material shows much more excellent catalytic activity than the non-etched Mo_(2)C/NC toward hydrogen evolution reaction(HER)in acidic medium.More interestingly mp-Mo_(2)C/NC still has larger overpotential than Pt/C at lower current densities,but possess remarkably smaller overpotential than the latter at higher current densities for much better electrocatalytic performance.An approach is developed to investigate the electrode kinetics by Tafel plots,especially with eliminating the diffusion effect,indicating that Pt/C and mp-Mo_(2)C/NC display different reaction mechanisms.At low current densities the former presents reversible reaction,while the latter shows mixed electrochemical polarization/reversible electrode process.In the region of higher current densities,the former becomes totally gas-diffusion controlled with large overpotential,while the latter can still retain an electrode polarization process for much lower overpotential at the same current density.Result endorses that the meso-porously structured mp-Mo_(2)C/NC plays a critical role in avoiding gas diffusion control-resulting large overpotential at high current densities.This work holds great potential for an inexpensive catalyst better than Pt/C in practical applications of mass-production hydrogen at high current densities,while clearly shedding fundamental lights on designs of rational HER catalysts for the uses at high current densities.
基金The authors would like to acknowledge the funding support to this research from the projects of ZE1W and BBAT from The Hong Kong Polytechnic University,the National Natural Science Foundation of China(NSFC)(Grant No.51835011)the General Research Fund(GRF)(Grant No.15223520).
文摘As one of the indispensable actuating components in micro-systems,the shafted microgear is in great production demand.Microforming is a manufacturing process to produce microgears to meet the needs.Due to the small geometrical size,there are uncertain process performance and product quality issues in this production process.In this study,the shafted microgears were fabricated in two different scaling factors with four grain sizes using a progressively extrusion-blanking method.To explore the unknown of the process,grain-based modeling was proposed and employed to simulate the entire forming process.The results show that when the grains are large,the anisotropy of single grains has an obvious size effect on the forming behavior and process performance;and the produced geometries and surface quality are worsened;and the deformation load is decreased.Five deformation zones were identified in the microstructures with different hardness and distributions of stress and strain.The simulation by using the proposed model successfully predicted the formation of zones and revealed the inhomogeneous deformation in the forming process.The undesirable geometries of microgears including material unfilling,burr and inclination were observed on the shaft and teeth of gear,and the inclination size is increased obviously with grain size.To avoid the formation of inclination and material unfilling,the punch was redesigned,and a die insert was added to constraint the bottom surface of the gear teeth.The new products had then the better forming quality.
基金Supported by the National Natural Science Foundation of China.
文摘The purpose of this paper is to study the long time asymptotic behavior for anonlinear Schrdinger equations with magnetic effect. Under certain conditions, we prove theexistence and nonexistence of the non-trivial free asymptotic solutions. In addition, the decayestimates of the solutions are also obtained.