Despite the growing demand for transparent conductive films in smart and wearable electronics for electromagnetic interference(EMI)shielding,achieving a flexible EMI shielding film,while maintaining a high transmittan...Despite the growing demand for transparent conductive films in smart and wearable electronics for electromagnetic interference(EMI)shielding,achieving a flexible EMI shielding film,while maintaining a high transmittance remains a significant challenge.Herein,a flexible,transparent,and conductive copper(Cu)metal mesh film for EMI shielding is fabricated by self-forming crackle template method and electroplating technique.The Cu mesh film shows an ultra-low sheet resistance(0.18Ω□^(-1)),high transmittance(85.8%@550 nm),and ultra-high figure of merit(>13,000).It also has satisfactory stretchability and mechanical stability,with a resistance increases of only 1.3%after 1,000 bending cycles.As a stretchable heater(ε>30%),the saturation temperature of the film can reach over 110°C within 60 s at 1.00 V applied voltage.Moreover,the metal mesh film exhibits outstanding average EMI shielding effectiveness of 40.4 dB in the X-band at the thickness of 2.5μm.As a demonstration,it is used as a transparent window for shielding the wireless communication electromagnetic waves.Therefore,the flexible and transparent conductive Cu mesh film proposed in this work provides a promising candidate for the next-generation EMI shielding applications.展开更多
Herein,we demonstrate the synthesis of bifunctional nickel cobalt selenide@nickel telluride(Ni_(x)Co_(12-x)Se@NiTe)core-shell heterostructures via an electrodeposition approach for overall urea electrolysis and superc...Herein,we demonstrate the synthesis of bifunctional nickel cobalt selenide@nickel telluride(Ni_(x)Co_(12-x)Se@NiTe)core-shell heterostructures via an electrodeposition approach for overall urea electrolysis and supercapacitors.The 3D vertically orientated NiTe dendritic frameworks induce the homogeneous nucleation of 2D Ni_(x)Co_(12-x)Se nanosheet arrays along similar crystal directions and bring a strong interfacial binding between the integrated active components.In particular,the optimized Ni_(6)Co_(6)Se@NiTe with an interface coupling effect works in concert to tune the intrinsic activity.It only needs a low overpotential of 1.33 V to yield a current density of 10 mA cm^(-2)for alkaline urea electrolysis.Meanwhile,the full urea catalysis driven only by Ni_(6)Co_(6)Se@NiTe achieves 10 mA cm^(-2)at a potential of 1.38 V and can approach a constant level of the current response for 40 h.Besides,the integrated Ni_(6)Co_(6)Se@NiTe electrode delivers an enhanced specific capacity(223 mA h g^(-1)at 1 A g^(-1))with a high cycling stability.Consequently,a hybrid asymmetric supercapacitor(HASC)device based on Ni_(6)Co_(6)Se@NiTe exhibits a favorable rate capability and reaches a high energy density of 67.7 Wh kg^(-1)and a power density of 724.8 W kg^(-1)with an exceptional capacity retention of 92.4%after sequential 12000 cycles at 5 A g^(-1).展开更多
Using Complete Coverage Path Planning (CCPP), a cleaning robot could visit every accessible area in the workspace. The dynamic environment requires the higher computation of the CCPP algorithm because the path needs...Using Complete Coverage Path Planning (CCPP), a cleaning robot could visit every accessible area in the workspace. The dynamic environment requires the higher computation of the CCPP algorithm because the path needs to be replanned when the path might become invalid. In previous CCPP methods, when the neighbours of the current position are obstacles or have been visited, it is challenging for the robot to escape from the deadlocks with the least extra time cost. In this study, a novel CCPP algorithm is proposed to deal with deadlock problems in a dynamic environment. A priority template inspired by the short memory model could reduce the number of deadlocks by giving the priority of directions. Simultaneously, a global backtracking mechanism guides the robot to move to the next unvisited area quickly, taking the use of the explored global environmental information. What's more, the authors extend their CCPP algorithm to a multi-robot system with a market-based bidding process which could deploy the coverage time. Experiments of apartment-like scenes show that the authors' proposed algorithm can guarantee an efficient collision-free coverage in dynamic environments. The proposed method performs better than related approaches on coverage rate and overlap length.展开更多
This study analyzes and gives advice on the relevant folk culture of Lingnan from the perspective of digital protection and inheritance, through the implementation of multimedia interaction scenarios and interaction p...This study analyzes and gives advice on the relevant folk culture of Lingnan from the perspective of digital protection and inheritance, through the implementation of multimedia interaction scenarios and interaction processes, the historical and cultural implications of the Lingnan heritage, the stories of local folklore and the simulation interaction of the production process are realized. This paper proposes a visual and realistic concept of Lingnan culture, and uses the multimedia design method of image animation, audio and other multimedia design methods to sense the virtual reality design, aiming at the historical background, folk culture, craft culture, business culture and so on. The core is vividly communicated to the public. Bringing the Lingnan people a more immersive and authentic cultural experience.展开更多
Economic Management Professional Academic Education are increasingly becoming personalization,intelligence and application.Colleges and universities should actively use cloud computing and big data.Also Internet of Th...Economic Management Professional Academic Education are increasingly becoming personalization,intelligence and application.Colleges and universities should actively use cloud computing and big data.Also Internet of Things and other advanced information technologies to build an economics and management ERP virtual simulation experiment teaching platform.Cloud computing and big data,virtual simulation experiment teaching resources with"resource library+project library+enterprise management simulation sandbox training"as the core can build an online and offline collaborative and practical experiment teaching platform.It is expected to achieve the ideal effect of integration of three spaces.Such as physics and resources and social digital teaching.Moreover,it can also benefit human-computer collaboration and interactive teaching and inquiry learning.展开更多
In thermoelectrics,phase engineering serves a crucial function in deter-mining the power factor by affecting the band degeneracy.However,for low-symmetry compounds,the mainstream one-step phase manipulation strategy,d...In thermoelectrics,phase engineering serves a crucial function in deter-mining the power factor by affecting the band degeneracy.However,for low-symmetry compounds,the mainstream one-step phase manipulation strategy,depending solely on the valley or orbital degeneracy,is inadequate to attain a high density-of-states effective mass and exceptional zT.Here,we employ a distinctive two-step phase manipulation strategy through stepwise tailoring chemical bonds in GeSe.Initially,we amplify the valley degeneracy via CdTe alloying,which elevates the crystal symmetry from a covalently bonded orthorhombic to a metavalently bonded rhombohedral phase by significantly suppressing the Peierls distortion.Subsequently,we incorporate Pb to trigger the convergence of multivalence bands and further enhance the density-of-states effective mass by moderately restraining the Peierls distortion.Additionally,the atypical metavalent bonding in rhombohedral GeSe enables a high Ge vacancy concentration and a small band effective mass,leading to increased carrier concentration and mobility.This weak chemical bond along with strong lattice anharmonicity also reduces lattice thermal conductivity.Consequently,this unique property ensemble contributes to an outstanding zT of 0.9 at 773 K for Geo.8oPbo.2oSe(CdTe)o.25.This work underscores the pivotal role of the two-step phase manipulation by stepwise tailoring of chemical bonds in improving the thermoelectric performance of p-bonded chalcogenides.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.523712475,2072415 and 62101352)Shenzhen Science and Technology Program(RCBS20210706092343016).
文摘Despite the growing demand for transparent conductive films in smart and wearable electronics for electromagnetic interference(EMI)shielding,achieving a flexible EMI shielding film,while maintaining a high transmittance remains a significant challenge.Herein,a flexible,transparent,and conductive copper(Cu)metal mesh film for EMI shielding is fabricated by self-forming crackle template method and electroplating technique.The Cu mesh film shows an ultra-low sheet resistance(0.18Ω□^(-1)),high transmittance(85.8%@550 nm),and ultra-high figure of merit(>13,000).It also has satisfactory stretchability and mechanical stability,with a resistance increases of only 1.3%after 1,000 bending cycles.As a stretchable heater(ε>30%),the saturation temperature of the film can reach over 110°C within 60 s at 1.00 V applied voltage.Moreover,the metal mesh film exhibits outstanding average EMI shielding effectiveness of 40.4 dB in the X-band at the thickness of 2.5μm.As a demonstration,it is used as a transparent window for shielding the wireless communication electromagnetic waves.Therefore,the flexible and transparent conductive Cu mesh film proposed in this work provides a promising candidate for the next-generation EMI shielding applications.
基金supported by the open fund of the National Defense Key Discipline Laboratory of New Micro/Nano Devices and System Technology,Zhejiang Provincial Natural Science Foundation of China,under Grant No.LY19E020014NSFC(Grant Nos 21303162 and 11604295)
文摘Herein,we demonstrate the synthesis of bifunctional nickel cobalt selenide@nickel telluride(Ni_(x)Co_(12-x)Se@NiTe)core-shell heterostructures via an electrodeposition approach for overall urea electrolysis and supercapacitors.The 3D vertically orientated NiTe dendritic frameworks induce the homogeneous nucleation of 2D Ni_(x)Co_(12-x)Se nanosheet arrays along similar crystal directions and bring a strong interfacial binding between the integrated active components.In particular,the optimized Ni_(6)Co_(6)Se@NiTe with an interface coupling effect works in concert to tune the intrinsic activity.It only needs a low overpotential of 1.33 V to yield a current density of 10 mA cm^(-2)for alkaline urea electrolysis.Meanwhile,the full urea catalysis driven only by Ni_(6)Co_(6)Se@NiTe achieves 10 mA cm^(-2)at a potential of 1.38 V and can approach a constant level of the current response for 40 h.Besides,the integrated Ni_(6)Co_(6)Se@NiTe electrode delivers an enhanced specific capacity(223 mA h g^(-1)at 1 A g^(-1))with a high cycling stability.Consequently,a hybrid asymmetric supercapacitor(HASC)device based on Ni_(6)Co_(6)Se@NiTe exhibits a favorable rate capability and reaches a high energy density of 67.7 Wh kg^(-1)and a power density of 724.8 W kg^(-1)with an exceptional capacity retention of 92.4%after sequential 12000 cycles at 5 A g^(-1).
基金This work was supported by the National Natural Science Foundation (NSFC, nos. 61340046, 61673030, U1613209), Natural Science Foundation of Guangdong Province (no. 2015A030311034), Scientific Research Project of Guangdong Province (no. 2015B010919004), Specialized Research Fund for Strategic and Prospective Industrial Development of Shenzhen City (no. ZLZBCXLJZI20160729020003), Shenzhen Key Laboratory for Intelligent Multimedia and Virtual Reality (ZDSYS201703031405467).
文摘Using Complete Coverage Path Planning (CCPP), a cleaning robot could visit every accessible area in the workspace. The dynamic environment requires the higher computation of the CCPP algorithm because the path needs to be replanned when the path might become invalid. In previous CCPP methods, when the neighbours of the current position are obstacles or have been visited, it is challenging for the robot to escape from the deadlocks with the least extra time cost. In this study, a novel CCPP algorithm is proposed to deal with deadlock problems in a dynamic environment. A priority template inspired by the short memory model could reduce the number of deadlocks by giving the priority of directions. Simultaneously, a global backtracking mechanism guides the robot to move to the next unvisited area quickly, taking the use of the explored global environmental information. What's more, the authors extend their CCPP algorithm to a multi-robot system with a market-based bidding process which could deploy the coverage time. Experiments of apartment-like scenes show that the authors' proposed algorithm can guarantee an efficient collision-free coverage in dynamic environments. The proposed method performs better than related approaches on coverage rate and overlap length.
文摘This study analyzes and gives advice on the relevant folk culture of Lingnan from the perspective of digital protection and inheritance, through the implementation of multimedia interaction scenarios and interaction processes, the historical and cultural implications of the Lingnan heritage, the stories of local folklore and the simulation interaction of the production process are realized. This paper proposes a visual and realistic concept of Lingnan culture, and uses the multimedia design method of image animation, audio and other multimedia design methods to sense the virtual reality design, aiming at the historical background, folk culture, craft culture, business culture and so on. The core is vividly communicated to the public. Bringing the Lingnan people a more immersive and authentic cultural experience.
基金the 2020 University Innovation and Entrepreneurship Project of Guangdong University of Foreign Studies.
文摘Economic Management Professional Academic Education are increasingly becoming personalization,intelligence and application.Colleges and universities should actively use cloud computing and big data.Also Internet of Things and other advanced information technologies to build an economics and management ERP virtual simulation experiment teaching platform.Cloud computing and big data,virtual simulation experiment teaching resources with"resource library+project library+enterprise management simulation sandbox training"as the core can build an online and offline collaborative and practical experiment teaching platform.It is expected to achieve the ideal effect of integration of three spaces.Such as physics and resources and social digital teaching.Moreover,it can also benefit human-computer collaboration and interactive teaching and inquiry learning.
基金National Natural Science Foundation of China(52071218)National Key R&D Program of China(2021YFB1507403)+2 种基金Shenzhen University 2035 Pro-gram for Excellent Research( 00000218)China Postdoctoral Science Foundation(2022M722170)Y.Y.and M.W.acknowledge support from the German Research Founda tion(Deutsche Forchungsgemeinschaft,DFG)within project SFB917.Y.Y.acknowledges financial support under the Excellence Strategy of the Federal Govemment and the L ander within the ERS RWTH StartUp grant(Grant No.StUpPD_392-21).The authors also appre-ciate the Instrumental Analysis Center of Shenzhen University.
文摘In thermoelectrics,phase engineering serves a crucial function in deter-mining the power factor by affecting the band degeneracy.However,for low-symmetry compounds,the mainstream one-step phase manipulation strategy,depending solely on the valley or orbital degeneracy,is inadequate to attain a high density-of-states effective mass and exceptional zT.Here,we employ a distinctive two-step phase manipulation strategy through stepwise tailoring chemical bonds in GeSe.Initially,we amplify the valley degeneracy via CdTe alloying,which elevates the crystal symmetry from a covalently bonded orthorhombic to a metavalently bonded rhombohedral phase by significantly suppressing the Peierls distortion.Subsequently,we incorporate Pb to trigger the convergence of multivalence bands and further enhance the density-of-states effective mass by moderately restraining the Peierls distortion.Additionally,the atypical metavalent bonding in rhombohedral GeSe enables a high Ge vacancy concentration and a small band effective mass,leading to increased carrier concentration and mobility.This weak chemical bond along with strong lattice anharmonicity also reduces lattice thermal conductivity.Consequently,this unique property ensemble contributes to an outstanding zT of 0.9 at 773 K for Geo.8oPbo.2oSe(CdTe)o.25.This work underscores the pivotal role of the two-step phase manipulation by stepwise tailoring of chemical bonds in improving the thermoelectric performance of p-bonded chalcogenides.