Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work...Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work.Both roll-off and roll-up effects of Vth were comparatively investigated on IGZO transistors with varied gate insulator(GI),source/drain(S/D),and device architecture.For IGZO transistors with thinner GI,the SCE was attenuated due to the enhanced gate controllability over the variation of channel carrier concentration,while the Vth roll-up became more noteworthy.The latter was found to depend on the relative ratio of S/D series resistance(R_(SD))over channel resistance(R_(CH)),as verified on transistors with different S/D.Thus,an ideal S/D engineering with small R_(SD)but weak dopant diffusion is highly expected during the downscaling of L and GI in IGZO transistors.展开更多
Electrochemical reduction of nitrate(NO_(3^(-)))serves as an eco-friendly friendly alternative to the conventional Haber-Bosch ammonia(NH_(3))synthesis process.The Cu electrocatalyst is widely recognized for its stron...Electrochemical reduction of nitrate(NO_(3^(-)))serves as an eco-friendly friendly alternative to the conventional Haber-Bosch ammonia(NH_(3))synthesis process.The Cu electrocatalyst is widely recognized for its strong adsorption capacity towards nitrate,but its limited H adsorption and slow hydrogenation of oxynitride intermediates hinder the efficiency of converting NO_(3^(-))into NH_(3).Herein,a series of nanocomposite catalysts composed of CuO nanostructure with low NiO content that grow in-situ on carbon paper(Cu O/Ni O_(x)-CP)were synthesized via hydrothermal method and calcination for enhanced nitrate electroreduction utilizing the strong nitrate adsorption capacity of copper and excellent water dissociation ability of NiO to supply hydrogen free radicals(·H).In-situ Raman spectroscopy reveals dynamic reconstruction of Cu/NiO_(x)during the electrochemical nitrate reduction process from Cu O/NiO_(x).Due to the synergistic effect of Cu and NiO,a high Faradaic efficiency(FE,~97.9%)and yield rate(YR,391.5μmol h^(-1)cm^(-2))of ammonia are achieved on CuO/NiO_(2.3%)-CP.Electron paramagnetic resonance(EPR)proves that the presence of Ni O enhances the generation of·H,which can be rapidly consumed during nitrate reduction process.Density functional theory(DFT)calculations indicate that the activation energy of Ni O(0.57 eV)is much lower than Cu(0.84 e V)for water splitting to generate·H,thus facilitating*NO hydrogenations.This drives us to create more effective catalysts for nitrate reduction under neutral conditions by promoting H2O dissociation.展开更多
Network traffic identification is critical for maintaining network security and further meeting various demands of network applications.However,network traffic data typically possesses high dimensionality and complexi...Network traffic identification is critical for maintaining network security and further meeting various demands of network applications.However,network traffic data typically possesses high dimensionality and complexity,leading to practical problems in traffic identification data analytics.Since the original Dung Beetle Optimizer(DBO)algorithm,Grey Wolf Optimization(GWO)algorithm,Whale Optimization Algorithm(WOA),and Particle Swarm Optimization(PSO)algorithm have the shortcomings of slow convergence and easily fall into the local optimal solution,an Improved Dung Beetle Optimizer(IDBO)algorithm is proposed for network traffic identification.Firstly,the Sobol sequence is utilized to initialize the dung beetle population,laying the foundation for finding the global optimal solution.Next,an integration of levy flight and golden sine strategy is suggested to give dung beetles a greater probability of exploring unvisited areas,escaping from the local optimal solution,and converging more effectively towards a global optimal solution.Finally,an adaptive weight factor is utilized to enhance the search capabilities of the original DBO algorithm and accelerate convergence.With the improvements above,the proposed IDBO algorithm is then applied to traffic identification data analytics and feature selection,as so to find the optimal subset for K-Nearest Neighbor(KNN)classification.The simulation experiments use the CICIDS2017 dataset to verify the effectiveness of the proposed IDBO algorithm and compare it with the original DBO,GWO,WOA,and PSO algorithms.The experimental results show that,compared with other algorithms,the accuracy and recall are improved by 1.53%and 0.88%in binary classification,and the Distributed Denial of Service(DDoS)class identification is the most effective in multi-classification,with an improvement of 5.80%and 0.33%for accuracy and recall,respectively.Therefore,the proposed IDBO algorithm is effective in increasing the efficiency of traffic identification and solving the problem of the original DBO algorithm that converges slowly and falls into the local optimal solution when dealing with high-dimensional data analytics and feature selection for network traffic identification.展开更多
Transition metal Ni anchored in carbon material represents outstanding 2e^(-) oxygen reduction reaction(ORR)catalytic selectivity,but enhancing the adsorption strength of intermediate*OOH to promote its selectivity re...Transition metal Ni anchored in carbon material represents outstanding 2e^(-) oxygen reduction reaction(ORR)catalytic selectivity,but enhancing the adsorption strength of intermediate*OOH to promote its selectivity remains a major challenge.Herein,the NiX/Ni@NCHS composite catalyst with heteroatom doping(O,S)is modulated by controlling partial pyrolysis strategies on honeycomb-like porous carbon to manipulate the electronic structure of the metal Ni.With the synergistic effect of honeycomb structure and O atom,NiO/Ni@NCHS-700 exhibits an exceptional H_(2)O_(2)selectivity of above 89.1%across a wide potential range from 0.1 to 0.6 V in an alkaline electrolyte,and an unexpected H_(2)O_(2)production rate up to 1.47 mol gcat^(-1) h^(-1)@0.2 V,which outperforms most of the state-of-the-art catalyst.Meanwhile,NiS/Ni@NCHS exhibits excellent electrocatalytic performance,with 2e^(-) ORR selectivity of 91.3%,H_(2)O_(2)yield of 1.85@0.3 V.Density functional theory simulations and experiments results reveal that the heteroatom doping(O,S)method has been employed to regulate the adsorption strength of Ni atoms with*OOH,and combined with the self-sacrificing template-assisted pyrolysis approach to improve the microstructure of catalysts and optimize the active site.The heteroatom doping method in this work provides significant guidance for promoting 2e^(-) ORR electrocatalysis to produce H_(2)O_(2).展开更多
Detecting low-frequency underwater acoustic signals can be a challenge for marine applications.Inspired by the notably strong response of the auditory organs of pectis jellyfish to ultralow frequencies,a kind of otoli...Detecting low-frequency underwater acoustic signals can be a challenge for marine applications.Inspired by the notably strong response of the auditory organs of pectis jellyfish to ultralow frequencies,a kind of otolith-inspired vector hydrophone(OVH)is developed,enabled by hollow buoyant spheres atop cilia.Full parametric analysis is performed to optimize the cilium structure in order to balance the resonance frequency and sensitivity.After the structural parameters of the OVH are determined,the stress distributions of various vector hydrophones are simulated and analyzed.The shock resistance of the OVH is also investigated.Finally,the OVH is fabricated and calibrated.The receiving sensitivity of the OVH is measured to be as high as−202.1 dB@100 Hz(0 dB@1 V/μPa),and the average equivalent pressure sensitivity over the frequency range of interest of the OVH reaches−173.8 dB when the frequency ranges from 20 to 200 Hz.The 3 dB polar width of the directivity pattern for the OVH is measured as 87°.Moreover,the OVH is demonstrated to operate under 10 MPa hydrostatic pressure.These results show that the OVH is promising in low-frequency underwater acoustic detection.展开更多
Summary What is already known about this topic?Consuming refined grains,specifically white rice,elevates the risk of developing type 2 diabetes(T2D).Conversely,incorporating whole grains into the diet is linked to a r...Summary What is already known about this topic?Consuming refined grains,specifically white rice,elevates the risk of developing type 2 diabetes(T2D).Conversely,incorporating whole grains into the diet is linked to a reduced risk.What is added by this report?This study employed a novel multi-trajectory modeling technique to account for the intercorrelations among various cereal consumption patterns.展开更多
基金supported financially by National key Research and Development Program under Grant 2021YFB3600802Shenzhen Municipal Scientific Program under Grant KJZD20230923114111021。
文摘Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work.Both roll-off and roll-up effects of Vth were comparatively investigated on IGZO transistors with varied gate insulator(GI),source/drain(S/D),and device architecture.For IGZO transistors with thinner GI,the SCE was attenuated due to the enhanced gate controllability over the variation of channel carrier concentration,while the Vth roll-up became more noteworthy.The latter was found to depend on the relative ratio of S/D series resistance(R_(SD))over channel resistance(R_(CH)),as verified on transistors with different S/D.Thus,an ideal S/D engineering with small R_(SD)but weak dopant diffusion is highly expected during the downscaling of L and GI in IGZO transistors.
基金supported by the National Natural Science Foundation of China(No.U22A20253)。
文摘Electrochemical reduction of nitrate(NO_(3^(-)))serves as an eco-friendly friendly alternative to the conventional Haber-Bosch ammonia(NH_(3))synthesis process.The Cu electrocatalyst is widely recognized for its strong adsorption capacity towards nitrate,but its limited H adsorption and slow hydrogenation of oxynitride intermediates hinder the efficiency of converting NO_(3^(-))into NH_(3).Herein,a series of nanocomposite catalysts composed of CuO nanostructure with low NiO content that grow in-situ on carbon paper(Cu O/Ni O_(x)-CP)were synthesized via hydrothermal method and calcination for enhanced nitrate electroreduction utilizing the strong nitrate adsorption capacity of copper and excellent water dissociation ability of NiO to supply hydrogen free radicals(·H).In-situ Raman spectroscopy reveals dynamic reconstruction of Cu/NiO_(x)during the electrochemical nitrate reduction process from Cu O/NiO_(x).Due to the synergistic effect of Cu and NiO,a high Faradaic efficiency(FE,~97.9%)and yield rate(YR,391.5μmol h^(-1)cm^(-2))of ammonia are achieved on CuO/NiO_(2.3%)-CP.Electron paramagnetic resonance(EPR)proves that the presence of Ni O enhances the generation of·H,which can be rapidly consumed during nitrate reduction process.Density functional theory(DFT)calculations indicate that the activation energy of Ni O(0.57 eV)is much lower than Cu(0.84 e V)for water splitting to generate·H,thus facilitating*NO hydrogenations.This drives us to create more effective catalysts for nitrate reduction under neutral conditions by promoting H2O dissociation.
基金supported by the National Natural Science Foundation of China under Grant 61602162the Hubei Provincial Science and Technology Plan Project under Grant 2023BCB041.
文摘Network traffic identification is critical for maintaining network security and further meeting various demands of network applications.However,network traffic data typically possesses high dimensionality and complexity,leading to practical problems in traffic identification data analytics.Since the original Dung Beetle Optimizer(DBO)algorithm,Grey Wolf Optimization(GWO)algorithm,Whale Optimization Algorithm(WOA),and Particle Swarm Optimization(PSO)algorithm have the shortcomings of slow convergence and easily fall into the local optimal solution,an Improved Dung Beetle Optimizer(IDBO)algorithm is proposed for network traffic identification.Firstly,the Sobol sequence is utilized to initialize the dung beetle population,laying the foundation for finding the global optimal solution.Next,an integration of levy flight and golden sine strategy is suggested to give dung beetles a greater probability of exploring unvisited areas,escaping from the local optimal solution,and converging more effectively towards a global optimal solution.Finally,an adaptive weight factor is utilized to enhance the search capabilities of the original DBO algorithm and accelerate convergence.With the improvements above,the proposed IDBO algorithm is then applied to traffic identification data analytics and feature selection,as so to find the optimal subset for K-Nearest Neighbor(KNN)classification.The simulation experiments use the CICIDS2017 dataset to verify the effectiveness of the proposed IDBO algorithm and compare it with the original DBO,GWO,WOA,and PSO algorithms.The experimental results show that,compared with other algorithms,the accuracy and recall are improved by 1.53%and 0.88%in binary classification,and the Distributed Denial of Service(DDoS)class identification is the most effective in multi-classification,with an improvement of 5.80%and 0.33%for accuracy and recall,respectively.Therefore,the proposed IDBO algorithm is effective in increasing the efficiency of traffic identification and solving the problem of the original DBO algorithm that converges slowly and falls into the local optimal solution when dealing with high-dimensional data analytics and feature selection for network traffic identification.
文摘Transition metal Ni anchored in carbon material represents outstanding 2e^(-) oxygen reduction reaction(ORR)catalytic selectivity,but enhancing the adsorption strength of intermediate*OOH to promote its selectivity remains a major challenge.Herein,the NiX/Ni@NCHS composite catalyst with heteroatom doping(O,S)is modulated by controlling partial pyrolysis strategies on honeycomb-like porous carbon to manipulate the electronic structure of the metal Ni.With the synergistic effect of honeycomb structure and O atom,NiO/Ni@NCHS-700 exhibits an exceptional H_(2)O_(2)selectivity of above 89.1%across a wide potential range from 0.1 to 0.6 V in an alkaline electrolyte,and an unexpected H_(2)O_(2)production rate up to 1.47 mol gcat^(-1) h^(-1)@0.2 V,which outperforms most of the state-of-the-art catalyst.Meanwhile,NiS/Ni@NCHS exhibits excellent electrocatalytic performance,with 2e^(-) ORR selectivity of 91.3%,H_(2)O_(2)yield of 1.85@0.3 V.Density functional theory simulations and experiments results reveal that the heteroatom doping(O,S)method has been employed to regulate the adsorption strength of Ni atoms with*OOH,and combined with the self-sacrificing template-assisted pyrolysis approach to improve the microstructure of catalysts and optimize the active site.The heteroatom doping method in this work provides significant guidance for promoting 2e^(-) ORR electrocatalysis to produce H_(2)O_(2).
基金supported by the National Natural Science Foundation of China(Grant 51875535 and 61727806)by 1331KSC,State Key Laboratory of Precision Measuring Technology and Instruments(pilab1805)。
文摘Detecting low-frequency underwater acoustic signals can be a challenge for marine applications.Inspired by the notably strong response of the auditory organs of pectis jellyfish to ultralow frequencies,a kind of otolith-inspired vector hydrophone(OVH)is developed,enabled by hollow buoyant spheres atop cilia.Full parametric analysis is performed to optimize the cilium structure in order to balance the resonance frequency and sensitivity.After the structural parameters of the OVH are determined,the stress distributions of various vector hydrophones are simulated and analyzed.The shock resistance of the OVH is also investigated.Finally,the OVH is fabricated and calibrated.The receiving sensitivity of the OVH is measured to be as high as−202.1 dB@100 Hz(0 dB@1 V/μPa),and the average equivalent pressure sensitivity over the frequency range of interest of the OVH reaches−173.8 dB when the frequency ranges from 20 to 200 Hz.The 3 dB polar width of the directivity pattern for the OVH is measured as 87°.Moreover,the OVH is demonstrated to operate under 10 MPa hydrostatic pressure.These results show that the OVH is promising in low-frequency underwater acoustic detection.
基金funded by the National Key R&D Program of Ministry of Science and Technology[Research project on dietary nutrition Assessment and intervention techniques(No.2020YFC2006300)].
文摘Summary What is already known about this topic?Consuming refined grains,specifically white rice,elevates the risk of developing type 2 diabetes(T2D).Conversely,incorporating whole grains into the diet is linked to a reduced risk.What is added by this report?This study employed a novel multi-trajectory modeling technique to account for the intercorrelations among various cereal consumption patterns.
