The directional production of benzene is achieved by the current-enhanced catalytic conversion of lignin. The synergistic effect between catalyst and current promotes the depolymerization of lignin and the selective r...The directional production of benzene is achieved by the current-enhanced catalytic conversion of lignin. The synergistic effect between catalyst and current promotes the depolymerization of lignin and the selective recombinant of the functional groups in the aromatic monomers. A high benzene yield of 175 gbenzene/kglignin was obtained with an excellent selectivity of 92.9 C-mol%. The process potentially provides a promising route for the production of basic petrochemical materials or high value-added chemicals using renewable biomass.展开更多
Ultra-stable piezoelectric nanogenerator(PENG)driven by environmental actuation sources with all-weather service capability is highly desirable.Here,the PENG based on N doped 4H-SiC nanohole arrays(NHAs)is proposed to...Ultra-stable piezoelectric nanogenerator(PENG)driven by environmental actuation sources with all-weather service capability is highly desirable.Here,the PENG based on N doped 4H-SiC nanohole arrays(NHAs)is proposed to harvest ambient energy under low/high temperature and relative humidity(RH)conditions.Finite element method simulation of N doped 4H-SiC NHAs in compression mode is developed to evaluate the relationship between nanohole diameter and piezoelectric performance.The density of short circuit current of the assembled PENG reaches 313 nA cm^(-2),which is 1.57 times the output of PENG based on N doped 4H-SiC nanowire arrays.The enhancement can be attributed to the existence of nanohole sidewalls in NHAs.All-weather service capability of the PENG is verified after being treated at-80/80℃and 0%/100%RH for 50 days.The PENG is promising to be widely used in practice worldwide to harvest biomechanical energy and mechanical energy.展开更多
The integration of numerous distributed energy resources and power electronic devices introduces a wide spectrum of frequency disturbances,which significantly challenge the stability of modern power systems.Therefore,...The integration of numerous distributed energy resources and power electronic devices introduces a wide spectrum of frequency disturbances,which significantly challenge the stability of modern power systems.Therefore,there is an urgent need to enhance the current monitoring level of modern power systems.This paper proposes a novel busbar current inversion scheme based on an elliptical magnetic sensor array.By establishing a simulation model,the effect of structural parameters of the elliptical array on its current measurement accuracy was analysed.The anti-interference capability of the elliptical array in complex environments such as busbar displacement and crosstalk was studied,and principles for designing array parameters under different current sensor standards were established.Experiments conducted on the proposed current sensing scheme demon-strated that the designed current array has a range of 0-150 A,with a current mea-surement error below 0.1% without external interference and not exceeding 1%during busbar displacement.Under conditions of crosstalk,the measurement accuracy achieved was class 0.5.The sensor array possesses high measurement accuracy,robust anti-interference capability,low power consumption,compact size and a noncontact nature.It exhibits significant potential for extensive application in novel business scenarios within the power system.展开更多
Quantum breakdown of superconductivity in low-dimensional superconducting systems has attracted enormous attention due to the underlying fluctuation.Here we report exotic phenomena observed during the current-induced ...Quantum breakdown of superconductivity in low-dimensional superconducting systems has attracted enormous attention due to the underlying fluctuation.Here we report exotic phenomena observed during the current-induced breakdown of superconductivity in gold nanowires contacted by superconducting electrodes.In a 1.0μm-long nanowire,the resistance as a function of current exhibits a random resistance switching at 1.8 K and tail-like metallic state at higher temperatures,indicating phase slips in proximity-induced superconducting nanowire.Additionally,the upper critical current is enhanced under low magnetic field,which may be attributed to the formation of spin-triplet pairing in superconducting gold nanowire.In a 1.2μm-long gold nanowire,unexpected subharmonic structures with characteristic energy smaller than superconducting gap are superimposed on tail-like structures.The signal might be related to the axions-triggered process in phase slip center Josephson junction and thus stimulate further studies in dissipative superconducting nanowires.展开更多
We propose a unique approach for realizing dopingless impact ionization MOS （DL-IMOS） based on the charge plasma concept as a remedy for complex process flow. It uses work-function engineering of electrodes to form ...We propose a unique approach for realizing dopingless impact ionization MOS （DL-IMOS） based on the charge plasma concept as a remedy for complex process flow. It uses work-function engineering of electrodes to form charge plasma as surrogate doping. This charge plasma induces a uniform p-region in the source side and an n-region in the drain side on intrinsic silicon film with a thickness less than the intrinsic Debye length. DL-IMOS offers a simple fabrication process flow as it avoids the need of ion implantation, photo masking and complicated thermal budget via annealing devices. The lower thermal budget is required for DL-IMOS fabrication enables its fabrication on single crystal silicon-on-glass substrate realized by wafer scale epitaxial transfer. It is highly immune to process variations, doping control issues and random dopant fluctuations, while retaining the inherent advantages of conventional IMOS. To epitomize the fabrication process flow for the proposed device a virtual fabrication flow is also proposed here. Extensive device simulation of the major device performance metrics such as subthreshold slope, threshold voltage, drain induced current enhancement, and breakdown voltage have been done for a wide range of electrodes work-function. To evaluate the potential applications of the proposed device at circuit level, its mixed mode simulations are also carried out.展开更多
文摘The directional production of benzene is achieved by the current-enhanced catalytic conversion of lignin. The synergistic effect between catalyst and current promotes the depolymerization of lignin and the selective recombinant of the functional groups in the aromatic monomers. A high benzene yield of 175 gbenzene/kglignin was obtained with an excellent selectivity of 92.9 C-mol%. The process potentially provides a promising route for the production of basic petrochemical materials or high value-added chemicals using renewable biomass.
基金This work was supported by the National Science Fund for Distinguished Young Scholars(No.52025041)the National Natural Science Foundation of China(No.51974021,51902020,51904021)+2 种基金the Fundamental Research Funds for the Central Universities of NO.FRF-TP-18-045A1 and FRF-TP-19-004B2Zthe National Postdoctoral Program for Innovative Talents(BX20180034)This project is supported by open foundation of Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials,Guangxi University(Grant No.2021GXYSOF12).
文摘Ultra-stable piezoelectric nanogenerator(PENG)driven by environmental actuation sources with all-weather service capability is highly desirable.Here,the PENG based on N doped 4H-SiC nanohole arrays(NHAs)is proposed to harvest ambient energy under low/high temperature and relative humidity(RH)conditions.Finite element method simulation of N doped 4H-SiC NHAs in compression mode is developed to evaluate the relationship between nanohole diameter and piezoelectric performance.The density of short circuit current of the assembled PENG reaches 313 nA cm^(-2),which is 1.57 times the output of PENG based on N doped 4H-SiC nanowire arrays.The enhancement can be attributed to the existence of nanohole sidewalls in NHAs.All-weather service capability of the PENG is verified after being treated at-80/80℃and 0%/100%RH for 50 days.The PENG is promising to be widely used in practice worldwide to harvest biomechanical energy and mechanical energy.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFB2402900Science and Technology Project of State Grid,Grant/Award Number:52060023001T。
文摘The integration of numerous distributed energy resources and power electronic devices introduces a wide spectrum of frequency disturbances,which significantly challenge the stability of modern power systems.Therefore,there is an urgent need to enhance the current monitoring level of modern power systems.This paper proposes a novel busbar current inversion scheme based on an elliptical magnetic sensor array.By establishing a simulation model,the effect of structural parameters of the elliptical array on its current measurement accuracy was analysed.The anti-interference capability of the elliptical array in complex environments such as busbar displacement and crosstalk was studied,and principles for designing array parameters under different current sensor standards were established.Experiments conducted on the proposed current sensing scheme demon-strated that the designed current array has a range of 0-150 A,with a current mea-surement error below 0.1% without external interference and not exceeding 1%during busbar displacement.Under conditions of crosstalk,the measurement accuracy achieved was class 0.5.The sensor array possesses high measurement accuracy,robust anti-interference capability,low power consumption,compact size and a noncontact nature.It exhibits significant potential for extensive application in novel business scenarios within the power system.
基金supported by the National Key Research and Development Program of China(Grant No.2018YFA0305604)the National Natural Science Foundation of China(Grant No.11888101)+2 种基金the Beijing Natural Science Foundation(Z180010)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB28000000)Penn State was supported by National Science Foundation grant DMR-0820404。
文摘Quantum breakdown of superconductivity in low-dimensional superconducting systems has attracted enormous attention due to the underlying fluctuation.Here we report exotic phenomena observed during the current-induced breakdown of superconductivity in gold nanowires contacted by superconducting electrodes.In a 1.0μm-long nanowire,the resistance as a function of current exhibits a random resistance switching at 1.8 K and tail-like metallic state at higher temperatures,indicating phase slips in proximity-induced superconducting nanowire.Additionally,the upper critical current is enhanced under low magnetic field,which may be attributed to the formation of spin-triplet pairing in superconducting gold nanowire.In a 1.2μm-long gold nanowire,unexpected subharmonic structures with characteristic energy smaller than superconducting gap are superimposed on tail-like structures.The signal might be related to the axions-triggered process in phase slip center Josephson junction and thus stimulate further studies in dissipative superconducting nanowires.
文摘We propose a unique approach for realizing dopingless impact ionization MOS （DL-IMOS） based on the charge plasma concept as a remedy for complex process flow. It uses work-function engineering of electrodes to form charge plasma as surrogate doping. This charge plasma induces a uniform p-region in the source side and an n-region in the drain side on intrinsic silicon film with a thickness less than the intrinsic Debye length. DL-IMOS offers a simple fabrication process flow as it avoids the need of ion implantation, photo masking and complicated thermal budget via annealing devices. The lower thermal budget is required for DL-IMOS fabrication enables its fabrication on single crystal silicon-on-glass substrate realized by wafer scale epitaxial transfer. It is highly immune to process variations, doping control issues and random dopant fluctuations, while retaining the inherent advantages of conventional IMOS. To epitomize the fabrication process flow for the proposed device a virtual fabrication flow is also proposed here. Extensive device simulation of the major device performance metrics such as subthreshold slope, threshold voltage, drain induced current enhancement, and breakdown voltage have been done for a wide range of electrodes work-function. To evaluate the potential applications of the proposed device at circuit level, its mixed mode simulations are also carried out.
