In this paper, we investigate the microfluid induced vibration of a nanotube in thermal environment. Attention is focused on a special case that the law of energy equipartition is unreliable unless the quantum effect ...In this paper, we investigate the microfluid induced vibration of a nanotube in thermal environment. Attention is focused on a special case that the law of energy equipartition is unreliable unless the quantum effect is taken into account. A nonlocal luler-Bernoulli beam model is used to model the transverse vibration of a single-walled nanotube （SWCNT）. Results reveal that the root of mean squared （RMS） amplitude of thermal vibration of the fluid-conveying SWCNT predicted from the quantum theory is lower than that predicted from the law of energy equipartition. The quantum effect on the thermal vibration of the fluid-conveying SWCNT is more significant for the cases of higher-order modes, lower flow velocity, lower temperature, and lower fluid density.展开更多
Atmospheric chemistry research and atmospheric measurement techniques have mutually promoted each other and developed rapidly in China in recent years.Cavity-based absorption spectroscopy,which uses a high-finesse cav...Atmospheric chemistry research and atmospheric measurement techniques have mutually promoted each other and developed rapidly in China in recent years.Cavity-based absorption spectroscopy,which uses a high-finesse cavity to achieve very long absorption path-length,thereby achieving ultra-high detection sensitivity,plays an extremely important role in atmospheric chemistry research.Based on the Beer–Lambert law,this technology has the unique advantages of being non-destructive,chemical-free,and highly selective.It does not require any sample preparation and can quantitatively analyze atmospheric trace gases in real time and in situ.In this paper,we review the following:(1)key technological advances in different cavity-based absorption spectroscopy techniques,including cavity ring-down spectroscopy,cavityenhanced absorption spectroscopy,cavity attenuated phase shift spectroscopy,and their extensions;and(2)applications of these techniques in the detection of atmospheric reactive species,such as total peroxy radical,formaldehyde,and reactive nitrogen(e.g.,NOx,HONO,peroxy nitrates,and alkyl nitrates).The review systematically introduces cavity-based absorption spectroscopy techniques and their applications in atmospheric chemistry,which will help promote further communication and cooperation in the fields of laser spectroscopy and atmospheric chemistry.展开更多
Metasurfaces offer exceptional capabilities for controlling electromagnetic waves,enabling the realization of unique electromagnetic properties.As communication technology continues to evolve,metasurfaces present prom...Metasurfaces offer exceptional capabilities for controlling electromagnetic waves,enabling the realization of unique electromagnetic properties.As communication technology continues to evolve,metasurfaces present promising applications in wireless communications.This paper reviews the latest advancements in metasurface research within the communication sector,explores metasurface-based wireless relay technologies,and summarizes various wireless communication methods employing different types of metasurfaces across diverse modulation schemes.This paper provides a detailed discussion on the design of wireless communication systems based on coding metasurfaces to simplify transmitter architecture,as well as the development of intelligent coding metasurfaces in the communication field.It also elaborates on the application of vector vortex light fields in metasurface communication.Finally,it offers a forward-looking perspective on wireless communication systems that incorporate coded metasurfaces.This review aims to furnish researchers with a thorough understanding of the current state and future directions of coded metasurface applications in communications.展开更多
Objective:Based on the CNKI database,this study analyzes the current research status and hotspots of the Timing it Right(TIR)Theory in China,providing insights and references for its further development in the field o...Objective:Based on the CNKI database,this study analyzes the current research status and hotspots of the Timing it Right(TIR)Theory in China,providing insights and references for its further development in the field of nursing.Methods:Using bibliometric methods and Citespace software,this study conducts a statistical and visual analysis of publications on TIR Theory from CNKI,focusing on annual publication volumes,author collaboration networks,high-frequency keywords,and emergent terms.Results:The study statistically analyzed the time distribution and research hotspots of 117 relevant papers.The annual publication volume shows a gradual upward trend,though the overall volume remains low.High-frequency keywords such as“family nursing,”“quality of life,”“acute myocardial infarction,”and“stroke”form the core research themes.Conclusion:Research on TIR Theory in China’s nursing field is still in the exploratory stage,and its attention and emphasis need to be enhanced.As it aligns with modern medical models,its application scope in nursing is expanding,promoting the high-quality,scientific,and diversified development of nursing services in China.展开更多
Wearable signal analysis is an important technology for monitoring physiological signals without interfering with an individual’s daily behavior.As detecting cardiovascular diseases can dramatically reduce mortality,...Wearable signal analysis is an important technology for monitoring physiological signals without interfering with an individual’s daily behavior.As detecting cardiovascular diseases can dramatically reduce mortality,arrhythmia recognition using ECG signals has attracted much attention.In this paper,we propose a singlechannel convolutional neural network to detect Atrial Fibrillation(AF)based on ECG signals collected by wearable devices.It contains 3 primary modules.All recordings are firstly uniformly sized,normalized,and Butterworth low-pass filtered for noise removal.Then the preprocessed ECG signals are fed into convolutional layers for feature extraction.In the classification module,the preprocessed signals are fed into convolutional layers containing large kernels for feature extraction,and the fully connected layer provides probabilities.During the training process,the output of the previous pooling layer is concatenated with the vectors of the convolutional layer as a new feature map to reduce feature loss.Numerous comparison and ablation experiments are performed on the 2017 PhysioNet/CinC Challenge dataset,demonstrating the superiority of the proposed method.展开更多
This article reviews the latest advances in the generation and control of perfect vector beams using metasurfaces.In recent years,metasurfaces have garnered increasing interest due to their simple fabrication and easy...This article reviews the latest advances in the generation and control of perfect vector beams using metasurfaces.In recent years,metasurfaces have garnered increasing interest due to their simple fabrication and easy integration.Perfect vortex beams(PVBs),as a type of vector beams,exhibit complex polarization states that require the superposition of multiple phases for their generation.The use of metasurfaces provides a compact platform for the generation of perfect vortex beams and enables more complex vortex beam control tasks,which are quite challenging for traditional optics.This paper begins by introducing the principle of perfect vortex beam generation using metasurfaces,followed by a discussion on the generation of complex perfect vortex beams,including multi-channel and grafted perfect vortex beams.Subsequently,it explores the applications of perfect vortex beams in particle trapping and optical communication.Finally,the paper summarizes the key findings,highlights the limitations of metasurfaces in perfect vortex beam applications,and provides insights into potential future research directions and applications.展开更多
This paper presents a new device integrating a nonlinear vibration absorber with a levitation magnetoelectric energy harvester for whole-spacecraft systems. This device effectively reduces vibration and has a stronger...This paper presents a new device integrating a nonlinear vibration absorber with a levitation magnetoelectric energy harvester for whole-spacecraft systems. This device effectively reduces vibration and has a stronger energy harvesting capability than the existing systems. It harvests energy from a wide frequency range and has a high output voltage. The harvested energy is determined by magnetic field strength, excitation frequency, and resistive load. The change in the magnetic field strength has the least impact on the output voltage. The vibration reduction effects and harvested energy of the system are analyzed with an approximate analytical method that combines the harmonic balance approach and the pseudo-arclength continuation algorithm. The results of the Runge-Kutta method are nearly consistent with those of the approximate analytical method. Moreover, the effects of the excitation frequency, resistive load, and parameters of the nonlinear energy sink on the system vibration response and energy harvesting are analyzed.展开更多
Spinal cord ischemia/reperfusion injury is a devastating medical disorder with poor prognosis that is associated with several pathophysiological conditions.However,multiple stimuli can trigger SCII,so the underlying m...Spinal cord ischemia/reperfusion injury is a devastating medical disorder with poor prognosis that is associated with several pathophysiological conditions.However,multiple stimuli can trigger SCII,so the underlying mechanism of this pathology has not yet been fully established.MicroRNAs(miRNAs)are a class of non-coding RNAs that mediate a variety of nervous system diseases and regulate numerous physiological functions,including apoptosis,autophagy,inflammation,and blood-spinal cord barrier damage.miRNA expression profiles are known to be altered after spinal cord ischemia/reperfusion injury.Therefore,gaining a better understanding of the significant roles that miRNAs play in spinal cord ischemia/reperfusion injury could help develop potential preventive and therapeutic strategies for spinal cord ischemia/reperfusion injury.This review summarizes the current state of our knowledge about the relationship between miRNAs and spinal cord ischemia/reperfusion injury,as well as potential miRNAs that could be targeted to treat spinal cord ischemia/reperfusion injury.展开更多
Significance of unstable species leaching was for the first time demonstrated on MOF-derived catalysts by taking PtNi-C as an example,that was instructive for the relevant catalyst fabrication and performance study.Pt...Significance of unstable species leaching was for the first time demonstrated on MOF-derived catalysts by taking PtNi-C as an example,that was instructive for the relevant catalyst fabrication and performance study.PtNi-C catalyst was synthesized by combining Pt nanoparticles with Ni-BTC after annealing in the tube furnace and the unstable Ni species can be easily leached out in nitric acid,and the stable PtNi nanoparticles trapped in the graphite carbon layer were obtained.The greatly improved catalytic ability for alcohol fuels oxidation was verified by comparing the fresh and acid leached catalysts in terms of the high peak current density,specific and mass activity and rapid charge transfer kinetics and high catalytic stability.The current work guides the importance of unstable assistant promoter removal for the MOF derived catalysts.展开更多
Graphene oxide(GO),an important chemical precursor of graphene,can stably disperse in aqueous surrounding and undergo aggregation as metal cations introduced.The usual instability of GO with ions is caused by the shie...Graphene oxide(GO),an important chemical precursor of graphene,can stably disperse in aqueous surrounding and undergo aggregation as metal cations introduced.The usual instability of GO with ions is caused by the shielding effect of ions and crosslinking between GO and ions.However,the dynamic stability of GO under ions exchange still remains unclear.Here,we investigated the dynamic dispersion stability of GO with metal ions and observed a redispersion behavior in concentrated Fe3+solution,other than permanent aggregation.The exchange with Fe3+ions drives the reversion of zeta(ζ)potential and enables the redispersion to individual GO-Fe3+complex sheets,following a dynamic electric double layer(EDL)mechanism.It is found that the specifically strong electrostatic shielding effect and coordination attraction between Fe3+and functional oxygen groups allows the selective redispersion of GO in concentrated Fe3+solution.The revealed dynamic dispersion stability complements our understanding on the dispersive stability of GO and can be utilized to fabricate graphene-metal hybrids for rich applications.展开更多
We report the development of a static magnetic eld Faraday rotation spectrometer for NO detection.A 5.33μm continuous-wave quantum cascade laser was used as the probing laser.Line absorption at 1875.81 cm^−1(2Π3=2Q(...We report the development of a static magnetic eld Faraday rotation spectrometer for NO detection.A 5.33μm continuous-wave quantum cascade laser was used as the probing laser.Line absorption at 1875.81 cm^−1(2Π3=2Q(3/2),v=1←0)was chosen for the detection.By using a Chernin type multipass cell,a detection precision of 1.15 ppbv(1σ,1s)was achieved with an absorption pathlength of 108 m.This value was reduced to 0.43 ppbv by increasing the data-acquisition time to 15 s.展开更多
基金supported by the National Natural Science Foundation of China (project nos.11672187 and 11402151)Natural Science Foundation of Liaoning Province (project no.201602573)Program for Liaoning Excellent Talents in University (no.LJQ2013020)
文摘In this paper, we investigate the microfluid induced vibration of a nanotube in thermal environment. Attention is focused on a special case that the law of energy equipartition is unreliable unless the quantum effect is taken into account. A nonlocal luler-Bernoulli beam model is used to model the transverse vibration of a single-walled nanotube （SWCNT）. Results reveal that the root of mean squared （RMS） amplitude of thermal vibration of the fluid-conveying SWCNT predicted from the quantum theory is lower than that predicted from the law of energy equipartition. The quantum effect on the thermal vibration of the fluid-conveying SWCNT is more significant for the cases of higher-order modes, lower flow velocity, lower temperature, and lower fluid density.
基金supported by the National Natural Science Foundation of China(Grant Nos.U21A2028,42022051,62275250,42030609,41627810,91644107,and 91544228).
文摘Atmospheric chemistry research and atmospheric measurement techniques have mutually promoted each other and developed rapidly in China in recent years.Cavity-based absorption spectroscopy,which uses a high-finesse cavity to achieve very long absorption path-length,thereby achieving ultra-high detection sensitivity,plays an extremely important role in atmospheric chemistry research.Based on the Beer–Lambert law,this technology has the unique advantages of being non-destructive,chemical-free,and highly selective.It does not require any sample preparation and can quantitatively analyze atmospheric trace gases in real time and in situ.In this paper,we review the following:(1)key technological advances in different cavity-based absorption spectroscopy techniques,including cavity ring-down spectroscopy,cavityenhanced absorption spectroscopy,cavity attenuated phase shift spectroscopy,and their extensions;and(2)applications of these techniques in the detection of atmospheric reactive species,such as total peroxy radical,formaldehyde,and reactive nitrogen(e.g.,NOx,HONO,peroxy nitrates,and alkyl nitrates).The review systematically introduces cavity-based absorption spectroscopy techniques and their applications in atmospheric chemistry,which will help promote further communication and cooperation in the fields of laser spectroscopy and atmospheric chemistry.
基金supported in part by National Natural Science Foundation of China(U24A20307 and 62175224)in part by the science and technology innovation leading talent project of special support plan for high-level talents in Zhejiang Province(2021R52032)+2 种基金in part by the China Jiliang University Basic Research ExpensesZhejiang University Students Science and Technology Innovation Activity Plan-New Talent Plan(2024R409C054)in part by the Natural Science Foundation of Zhejiang Province under Grant(ZCLZ25F0502).
文摘Metasurfaces offer exceptional capabilities for controlling electromagnetic waves,enabling the realization of unique electromagnetic properties.As communication technology continues to evolve,metasurfaces present promising applications in wireless communications.This paper reviews the latest advancements in metasurface research within the communication sector,explores metasurface-based wireless relay technologies,and summarizes various wireless communication methods employing different types of metasurfaces across diverse modulation schemes.This paper provides a detailed discussion on the design of wireless communication systems based on coding metasurfaces to simplify transmitter architecture,as well as the development of intelligent coding metasurfaces in the communication field.It also elaborates on the application of vector vortex light fields in metasurface communication.Finally,it offers a forward-looking perspective on wireless communication systems that incorporate coded metasurfaces.This review aims to furnish researchers with a thorough understanding of the current state and future directions of coded metasurface applications in communications.
文摘Objective:Based on the CNKI database,this study analyzes the current research status and hotspots of the Timing it Right(TIR)Theory in China,providing insights and references for its further development in the field of nursing.Methods:Using bibliometric methods and Citespace software,this study conducts a statistical and visual analysis of publications on TIR Theory from CNKI,focusing on annual publication volumes,author collaboration networks,high-frequency keywords,and emergent terms.Results:The study statistically analyzed the time distribution and research hotspots of 117 relevant papers.The annual publication volume shows a gradual upward trend,though the overall volume remains low.High-frequency keywords such as“family nursing,”“quality of life,”“acute myocardial infarction,”and“stroke”form the core research themes.Conclusion:Research on TIR Theory in China’s nursing field is still in the exploratory stage,and its attention and emphasis need to be enhanced.As it aligns with modern medical models,its application scope in nursing is expanding,promoting the high-quality,scientific,and diversified development of nursing services in China.
基金funded by the National Natural Science Foundation of China(No.62171114)the Fundamental Research Funds for the Central Universities(No.DUT22RC(3)099)Xiaomi Young Talents Program.
文摘Wearable signal analysis is an important technology for monitoring physiological signals without interfering with an individual’s daily behavior.As detecting cardiovascular diseases can dramatically reduce mortality,arrhythmia recognition using ECG signals has attracted much attention.In this paper,we propose a singlechannel convolutional neural network to detect Atrial Fibrillation(AF)based on ECG signals collected by wearable devices.It contains 3 primary modules.All recordings are firstly uniformly sized,normalized,and Butterworth low-pass filtered for noise removal.Then the preprocessed ECG signals are fed into convolutional layers for feature extraction.In the classification module,the preprocessed signals are fed into convolutional layers containing large kernels for feature extraction,and the fully connected layer provides probabilities.During the training process,the output of the previous pooling layer is concatenated with the vectors of the convolutional layer as a new feature map to reduce feature loss.Numerous comparison and ablation experiments are performed on the 2017 PhysioNet/CinC Challenge dataset,demonstrating the superiority of the proposed method.
基金supported by the Natural Science Foundation of Zhejiang Province(China)under Grant LY22F050001in part by the Science and technology innovation leading talent project of special support plan for high-level talents in Zhejiang Province(China)(2021R52032)in part by the National Natural Science Foundation of China under grant No.62175224.
文摘This article reviews the latest advances in the generation and control of perfect vector beams using metasurfaces.In recent years,metasurfaces have garnered increasing interest due to their simple fabrication and easy integration.Perfect vortex beams(PVBs),as a type of vector beams,exhibit complex polarization states that require the superposition of multiple phases for their generation.The use of metasurfaces provides a compact platform for the generation of perfect vortex beams and enables more complex vortex beam control tasks,which are quite challenging for traditional optics.This paper begins by introducing the principle of perfect vortex beam generation using metasurfaces,followed by a discussion on the generation of complex perfect vortex beams,including multi-channel and grafted perfect vortex beams.Subsequently,it explores the applications of perfect vortex beams in particle trapping and optical communication.Finally,the paper summarizes the key findings,highlights the limitations of metasurfaces in perfect vortex beam applications,and provides insights into potential future research directions and applications.
基金the National Natural Science Foundation of China (Project No. 11772205)the Training Project of Liaoning Provincial Higher Education Institutions in Domestic and Overseas (Project No. 2018LNGXGJWPY-YB008)the Scientific Research Fund of Liaoning Provincial Education Department (Project No. L201703).
文摘This paper presents a new device integrating a nonlinear vibration absorber with a levitation magnetoelectric energy harvester for whole-spacecraft systems. This device effectively reduces vibration and has a stronger energy harvesting capability than the existing systems. It harvests energy from a wide frequency range and has a high output voltage. The harvested energy is determined by magnetic field strength, excitation frequency, and resistive load. The change in the magnetic field strength has the least impact on the output voltage. The vibration reduction effects and harvested energy of the system are analyzed with an approximate analytical method that combines the harmonic balance approach and the pseudo-arclength continuation algorithm. The results of the Runge-Kutta method are nearly consistent with those of the approximate analytical method. Moreover, the effects of the excitation frequency, resistive load, and parameters of the nonlinear energy sink on the system vibration response and energy harvesting are analyzed.
文摘Spinal cord ischemia/reperfusion injury is a devastating medical disorder with poor prognosis that is associated with several pathophysiological conditions.However,multiple stimuli can trigger SCII,so the underlying mechanism of this pathology has not yet been fully established.MicroRNAs(miRNAs)are a class of non-coding RNAs that mediate a variety of nervous system diseases and regulate numerous physiological functions,including apoptosis,autophagy,inflammation,and blood-spinal cord barrier damage.miRNA expression profiles are known to be altered after spinal cord ischemia/reperfusion injury.Therefore,gaining a better understanding of the significant roles that miRNAs play in spinal cord ischemia/reperfusion injury could help develop potential preventive and therapeutic strategies for spinal cord ischemia/reperfusion injury.This review summarizes the current state of our knowledge about the relationship between miRNAs and spinal cord ischemia/reperfusion injury,as well as potential miRNAs that could be targeted to treat spinal cord ischemia/reperfusion injury.
基金supported by the National Natural Science Foundation of China(Nos.21603041,21972124)the Priority Academic Program Development of Jiangsu Higher Education Institutionthe support of the Foundation of Excellent Doctoral Dissertation of Yangzhou University。
文摘Significance of unstable species leaching was for the first time demonstrated on MOF-derived catalysts by taking PtNi-C as an example,that was instructive for the relevant catalyst fabrication and performance study.PtNi-C catalyst was synthesized by combining Pt nanoparticles with Ni-BTC after annealing in the tube furnace and the unstable Ni species can be easily leached out in nitric acid,and the stable PtNi nanoparticles trapped in the graphite carbon layer were obtained.The greatly improved catalytic ability for alcohol fuels oxidation was verified by comparing the fresh and acid leached catalysts in terms of the high peak current density,specific and mass activity and rapid charge transfer kinetics and high catalytic stability.The current work guides the importance of unstable assistant promoter removal for the MOF derived catalysts.
基金supported by the National Natural Science Foundation of China(Nos.51533008,51603183,51703194,51803177,21805242 and 5197030056)National Key R&D Program of China(No.2016YFA0200200)+4 种基金Fujian Provincial Science and Technology Major Projects(No.2018HZ0001-2)Hundred Talents Program of Zhejiang University(No.188020*194231701/113)Key Research and Development Plan of Zhejiang Province(No.2018C01049)the Fundamental Research Funds for the Central Universities(Nos.2017QNA4036,2017XZZX001-04)Foundation of National Key Laboratory on Electromagnetic Environment Effects(No.614220504030717)。
文摘Graphene oxide(GO),an important chemical precursor of graphene,can stably disperse in aqueous surrounding and undergo aggregation as metal cations introduced.The usual instability of GO with ions is caused by the shielding effect of ions and crosslinking between GO and ions.However,the dynamic stability of GO under ions exchange still remains unclear.Here,we investigated the dynamic dispersion stability of GO with metal ions and observed a redispersion behavior in concentrated Fe3+solution,other than permanent aggregation.The exchange with Fe3+ions drives the reversion of zeta(ζ)potential and enables the redispersion to individual GO-Fe3+complex sheets,following a dynamic electric double layer(EDL)mechanism.It is found that the specifically strong electrostatic shielding effect and coordination attraction between Fe3+and functional oxygen groups allows the selective redispersion of GO in concentrated Fe3+solution.The revealed dynamic dispersion stability complements our understanding on the dispersive stability of GO and can be utilized to fabricate graphene-metal hybrids for rich applications.
基金supported by the National Key Research and Development Program of China(No.2016YFC0202205)the National Natural Science Foundation of China(No.41805104,No.41875151,and No.41627810)+2 种基金the Natural Science Foundation of Anhui Province(No.1508085J03)the Youth Innovation Promotion Association CAS(No.2016383)the CASHIPS Director's Fund(YZJJ2018QN7,BJPY2019B02).
文摘We report the development of a static magnetic eld Faraday rotation spectrometer for NO detection.A 5.33μm continuous-wave quantum cascade laser was used as the probing laser.Line absorption at 1875.81 cm^−1(2Π3=2Q(3/2),v=1←0)was chosen for the detection.By using a Chernin type multipass cell,a detection precision of 1.15 ppbv(1σ,1s)was achieved with an absorption pathlength of 108 m.This value was reduced to 0.43 ppbv by increasing the data-acquisition time to 15 s.
