Carbon nanotubes have attracted extensive interest owing to their extraordinary properties and wide applications in many fields.Among various types of carbon nanotubes,only ultralong carbon nanotubes with macroscale l...Carbon nanotubes have attracted extensive interest owing to their extraordinary properties and wide applications in many fields.Among various types of carbon nanotubes,only ultralong carbon nanotubes with macroscale lengths,low defect concentrations,and high degrees of alignment can fully demonstrate their intrinsic performance.These attributes make ultralong carbon nanotubes highly promising for applications in cutting-edge fields,such as carbon-based integrated circuits,ultra-strong fibers,and transparent conductive films.However,the mass production of ultralong carbon nanotubes with precise structural control remains a major challenge,limiting their widespread applications.In the past decades,great progress has been achieved in the study of ultralong carbon nanotubes.In this review,we summarized the growth mechanisms and the controlled synthesis strategies of ultralong carbon nanotubes.Then,we introduced the advanced applications of ultralong carbon nanotubes in many areas,such as field-effect transistors,sensors,and photodetectors.Finally,we discussed the remaining challenges and offered our perspectives on the future directions of this field.展开更多
Emerging monolayer molecular crystals(MMCs)have become prosperous in recent decades due to their numerous advantages.First,downsizing the active layer thickness to monolayer in organic field-effect transistors(OFETs)i...Emerging monolayer molecular crystals(MMCs)have become prosperous in recent decades due to their numerous advantages.First,downsizing the active layer thickness to monolayer in organic field-effect transistors(OFETs)is beneficial to elucidate the intrinsic charge-transport behavior.Next,the ultrathin conducting channel can reduce bulk injection resistance to extract mobility accurately.Then,direct exposure of the conducting channel can enhance the sensing performance.Finally,MMCs combine the merits of ultrathin thickness and high crystallization,which will improve the optoelectronic performance and realize complex device architectures for future advanced optoelectronic applications.In this Review,recent research progress in precise preparations and advanced applications of solution-processed MMCs are summarized.We present the current challenges related to MMCs with specific structures and desired performances,and an outlook regarding their application in next-generation integrated organic optoelectronics is provided.展开更多
Covalent organic framework(COF)monolayers,with atomically thin,ordered networks,and rich functionality,are widely studied due to their unusual structure/property relationships.However,synthesizing COF monolayer has re...Covalent organic framework(COF)monolayers,with atomically thin,ordered networks,and rich functionality,are widely studied due to their unusual structure/property relationships.However,synthesizing COF monolayer has remained an unmet challenge due to the difficulty of controlling reactions at the monolayer limit with large-scale uniformity.The identification and development of new reactions and polymerization conditions are critical for the further advancement of COF monolayer materials.Moreover,as one-molecule-thick a freestanding films,COF monolayer offers an ideal material system.Many advanced applications of COF monolayer have been explored in recent literature.This review provides an overview of the current state of precise synthetic strategies for COF monolayer,highlighting the advantages and limitations of different synthetic approaches and key challenges related to enhancing quality,and emphasizing the unique benefits of COF monolayer as both an ideal model system and for advanced applications.展开更多
Hydrogels,which are three-dimensional networks of crosslinked hydrophilic polymers,have become crucial for various advanced applications owing to their exceptional water absorption and swelling properties.This review ...Hydrogels,which are three-dimensional networks of crosslinked hydrophilic polymers,have become crucial for various advanced applications owing to their exceptional water absorption and swelling properties.This review explores the applications of hydrogels based on their unique swelling properties,beyond their application in traditional drug delivery,focusing on atmospheric water harvesting,hydrogel actuator,expansion microscopy(ExM),and 3D nanofabrication through controlled deswelling.We first discuss the factors influencing hydrogel swelling,such as network size and polymer properties.Next,we explore the mechanisms underlying hydrogel swelling,emphasizing the interplay between various forces.Hydrogel swelling enables ExM for super-resolution imaging of biological tissues,while controlled deswelling of hydrogels facilitates the creation of intricate 3D structures with nanoscale precision—a breakthrough for additive manufacturing techniques.Despite these advantages,challenges still remain.We conclude this review by emphasizing the need for interdisciplinary research to address these limitations and unlock the full potential of the hydrogel technology.The future of hydrogel research holds promise for revolutionary contributions to environmental science,robotics,and biomedical imaging.展开更多
This paper presents a review of the position-sensitive detector(PSD) sensor, covering different types of PSD and recent works related to this field. Furthermore, it explains the theoretical concepts and provides infor...This paper presents a review of the position-sensitive detector(PSD) sensor, covering different types of PSD and recent works related to this field. Furthermore, it explains the theoretical concepts and provides information about its structure and principles of operation. Moreover, it includes the main information about the available commercial PSDs from different companies, along with a comparison between the common modules. The PSD features include high position resolution, fast response, and a wide dynamic range. These features make it suitable for various fields and applications, such as imaging, spectrometry, spectroscopy and others.展开更多
Facility management and maintenance of the Thermal-Energy-Storage Air-Conditioning(TES-AC)system is a tedious task at a large scale mainly due to the charging load that can increase energy consumption if needed to be ...Facility management and maintenance of the Thermal-Energy-Storage Air-Conditioning(TES-AC)system is a tedious task at a large scale mainly due to the charging load that can increase energy consumption if needed to be charged at peak hours.Besides,maintenance of TES-AC at a large scale gets complex as it contains many sensor data.By utilizing deep learning techniques on the sensor data,charging load prediction can be made possible,so facility managers can prepare in advance.However,a deep learning-based application will be unusable if it is not deployed in a user-friendly manner where facility managers can benefit from this application.Hence,this research focuses on gathering design guidelines for a deep learning-based application and further validates the design considerations with a developed application for efficient human-computer interaction through qualitative analysis.The approach taken to gather design guidelines demonstrated a positive correlation between expert-suggested features and the user-friendly aspect of the application as 67.08%of participants found the features suggested by experts to be most satisfactory.Furthermore,it evaluates user satisfaction with the advanced developed application for TES-AC according to the gathered design guidelines.展开更多
The theoretical research of cable-driven mechanisms is developed with its broad applications. The first prototype of cable-driven mechanisms is RoboCrane, which was developed by the National Institute of Standards and...The theoretical research of cable-driven mechanisms is developed with its broad applications. The first prototype of cable-driven mechanisms is RoboCrane, which was developed by the National Institute of Standards and Technology （NIST）. Then many excellent properties were developed and they have a variety of applications such as aerospace, aircraft and automobile industries [1]. Example application for RoboCrane in the field of aircraft mainte- nance is equipped with a quick-change mechanism to remove the robot arm remotely.展开更多
The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising...The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising with increasing frequency in widely different areas, which cannot be addressed using conventional control techniques. The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where presence of large uncertainties as well as nonlinearities plays a major role. For instance, the design of unmanned aircraft, unmanned underwater vehicles, and automatic driving systems for automobiles are all typical examples of such difficult control problems. The large uncertainties concerning the plant may arise due to large external disturbances, large parameter variations because of faults in the system, or failure of some of the subsystems. In such cases, the controller has to determine the specific situation that exists at any instant, and take the appropriate control action. Accomplishing this rapidly, accurately, and in a stable fashion is the objective of control design.展开更多
Computational seismology is a relatively new interdisciplinary field spanning computational techniques in theoretical and observational seismology. It studies numerical methods and their implementation in various theo...Computational seismology is a relatively new interdisciplinary field spanning computational techniques in theoretical and observational seismology. It studies numerical methods and their implementation in various theoretical and applied problems in seismology.展开更多
Pulse tube cryocoolers working at liquid helium temperatures(LHe-PTCs),particularly those in a separated configuration-where the rotary valve assembly is positioned remotely from the cold head-exhibit high reliability...Pulse tube cryocoolers working at liquid helium temperatures(LHe-PTCs),particularly those in a separated configuration-where the rotary valve assembly is positioned remotely from the cold head-exhibit high reliability,long service life,low vibration,and strong resistance to electromagnetic interference.These characteristics make them indispensable for cryogen-free systems.Separated LHe-PTCs are widely used in advanced applications such as quantum physics[1]and particle physics[2],serving as core components in instruments including dilution refrigerators,scanning tunneling microscopes(STM),and superconducting magnet systems.展开更多
Considering the growing concerns about natural resource depletion,energy inequality,and climate crises,biomassderived materials—the most abundant organic matter on the planet—have received a lot of attention as a po...Considering the growing concerns about natural resource depletion,energy inequality,and climate crises,biomassderived materials—the most abundant organic matter on the planet—have received a lot of attention as a potential alternative to petroleum-based plastics.Herbaceous biomasses and extracted cellulose have recently been extensively used in the development of high-performance and multifunctional materials.Herbaceous biomass has sparked interest due to its species diversity,abundance,low cost,lightweight,and sustainability.This review discusses the structure versus property relationships of various sources of herbaceous biomasses(e.g.,sugarcane,straw,and bamboo)and their extracted biomaterials,as well as the latest emerging applications from macro-and microscales to nanoscales.High-strength structural materials,porous carbon materials,multichannel materials,and flexible materials are examples of these applications,which include sustainable electronics,environmentally friendly energy harvesting,smart materials,and biodegradable structural buildings.展开更多
In the wave of the Internet era created by computer and communication technology,flexible sensors play an important role in accurately collecting information owing to their excellent flexibility,ductility,freeform ben...In the wave of the Internet era created by computer and communication technology,flexible sensors play an important role in accurately collecting information owing to their excellent flexibility,ductility,freeform bending or folding,and versatile structural shapes.By endowing elastomeric polymers with conductivity,researchers have recently devoted extensive efforts toward developing high-performance flexible sensors based on elastomeric conductive layers and exploring their potential applications in diverse fields ranging from project manufacturing to daily life.This review reports the recent advancements in elastomeric polymers used to make conductive layers,as well as the relationships between elastomeric polymers and the performance and application of flexible sensors are comprehensively summarized.First,the principles and methods for using elastomeric polymers to construct conductive layers are provided.Then,the fundamental design,unique properties,and underlying mechanisms in different flexible sensors(pressure/strain,temperature,humidity)and their related applications are revealed.Finally,this review concludes with a perspective on the challenges and future directions of high-performance flexible sensors.展开更多
CONSPECTUS:Ultraviolet(UV)light,spanning wavelengths from 10 to 400 nm,is ubiquitous in military,livelihood,and scientific domains.Accurate UV photodetection is therefore essential for monitoring environmental radiati...CONSPECTUS:Ultraviolet(UV)light,spanning wavelengths from 10 to 400 nm,is ubiquitous in military,livelihood,and scientific domains.Accurate UV photodetection is therefore essential for monitoring environmental radiation,safeguarding human health,and advancing technological applications in fields such as aerospace,medical science,and ecology.The fabrication of high-performance UV photodetection devices fundamentally depends on the development of high-sensitivity UV photosensitive materials.The evolution of UV photodetection materials has progressed from early wide-bandgap semiconductors like ZnS and ZnSe to third-generation semiconductors such as GaN and Ga_(2)O_(3),and most recently to two-dimensional(2D)wide-bandgap materials that combine exceptional optoelectronic properties with compelling physicochemical properties.Among these,2D perovskite oxides stand out due to their prominent advantages for UV detection.First,this large family of materials generally features wide bandgaps,strong UV absorption,and high spectral selectivity.Second,the tunable bandgaps of 2D perovskite oxides enable precise detection at specific wavelengths.Third,their excellent processability and flexibility facilitate feasible integration into devices,making them promising candidates for flexible photodetectors.Furthermore,2D perovskite oxides boast other properties such as high stability,dielectricity,ferroelectricity,and biocompatibility.These characteristics have promoted the blossoming of 2D perovskite oxides for highperformance UV photodetection and are poised to expand their applications in novel functional optoelectronics.In this Account,we systematically review the development of 2D perovskite oxides,with a focus on their application in the fabrication of high-performance UV photodetectors.First,we describe the top-down synthesis of these materials,highlighting key advances in synthesis techniques.Second,we specifically analyze the intrinsic advantages of 2D perovskite oxides which render them highly suitable for UV detection.Third,we discuss recent progress in the fabrication of UV photodetectors based on 2D perovskite oxides,emphasizing effective strategies for achieving high-performance devices.Next,we explore state-of-the-art optoelectronic applications leveraging these materials.Finally,we present our perspectives on the future development of this promising class of UVsensitive materials.Given their remarkable material diversity,we believe that this Account will provide valuable insights to guide future research and the application of 2D perovskite oxides in high-performance UV photodetectors and functional optoelectronics.展开更多
Electron-induced colour routers actively manipulate dichromatic photon momentum at deep subwavelength scales,enabling programmable encrypted displays with enhanced security and high integration for advanced photonic a...Electron-induced colour routers actively manipulate dichromatic photon momentum at deep subwavelength scales,enabling programmable encrypted displays with enhanced security and high integration for advanced photonic applications.展开更多
Transmission loss of holey fiber is found to depend on its structure, and to be caused by Rayleigh scattering at glass surface. Under this loss dependence, most promising is optical wiring application, for which fiber...Transmission loss of holey fiber is found to depend on its structure, and to be caused by Rayleigh scattering at glass surface. Under this loss dependence, most promising is optical wiring application, for which fiber designs to realize bend-insensitivity and single-modedness are presented.展开更多
In this paper,an all-fiberized and narrow-linewidth 5 kW power-level fiber amplifier is presented.The laser is achieved based on the master oscillator power amplification configuration,in which the phase-modulated sin...In this paper,an all-fiberized and narrow-linewidth 5 kW power-level fiber amplifier is presented.The laser is achieved based on the master oscillator power amplification configuration,in which the phase-modulated single-frequency laser is applied as the seed laser and a bidirectional pumping configuration is applied in the power amplifier.The stimulated Brillouin scattering,stimulated Raman scattering,and transverse mode instability effects are all effectively suppressed in the experiment.Consequently,the output power is scaled up to 4.92 kW with a slope efficiency of as high as approximately 80%.The 3-dB spectral width is about 0.59 nm,and the beam quality is measured to be M^(2)~1.22 at maximum output power.Furthermore,we have also conducted a detailed spectral analysis on the spectral width of the signal laser,which reveals that the spectral wing broadening phenomenon could lead to the obvious decrease of the spectral purity at certain output power.Overall,this work could provide a reference for obtaining and optimizing high-power narrow-linewidth fiber lasers.展开更多
Recent results in the development of diode-driven high energy, high repetition rate, picosecond lasers, including the demonstration of a cryogenic Yb:YAG active mirror amplifier that produces 1.5 J pulses at 500 Hz re...Recent results in the development of diode-driven high energy, high repetition rate, picosecond lasers, including the demonstration of a cryogenic Yb:YAG active mirror amplifier that produces 1.5 J pulses at 500 Hz repetition rate(0.75 kW average power) are reviewed. These pulses are compressed resulting in the generation of ~5 ps duration,1 J pulses with 0.5 kW average power. A full characterization of this high power cryogenic amplifier, including atwavelength interferometry of the active region under >1 kW average power pump conditions, is presented. An initial demonstration of operation at 1 kW average power(1 J, 1 k Hz) is reported.展开更多
The increasing demana for advanced modelling methods, which can reflect complex travel activities of individuals, requires enhanced travel data collection methods. The introduction of GPS-assisted data collection meth...The increasing demana for advanced modelling methods, which can reflect complex travel activities of individuals, requires enhanced travel data collection methods. The introduction of GPS-assisted data collection methods has provided an alternative to the conventional methods of travel data collection. GPS-assisted data collection methods improve the accu- racy of data collection and enable capturing more details of individuals＇ travel behaviour. Recent technological advancements in smartphone-based positioning technologies and communication facilities have opened up new opportunities to apply smartphones as the media of GPS-assisted data collection. Although, different GPS-assisted methods have been employed recently, their performance has not been widely evaluated in real-world experi- ments compared to traditional data collection methods. Accordingly, this paper evaluates the performance of three GPS-assisted methods, namely handheld GPS tracking, smart- phone-based GPS tracking and smartphone-based prompted-recall data collection methods, in conjunction with the web-based data collection to shed light on different aspects of GPS- assisted data collection methods. These methods are compared in terms of the quality and accuracy of the collected data, the demographic attributes of participants and the specifi- cations of labelled trips. The results show that an appropriate employment of smartphones enhances the accuracy of data collection. It is also found that putting an extra burden on participants during a travel data collection survey results in lower trip-rates and poor data quality. Finally, it is found that the application of smartphone-assisted data collection methods help reporting non-motorised trips more accurately.展开更多
基金supported by the National Key Research and Development Program(Grant Nos.2020YFC2201103 and 2020YFA0210702)the National Natural Science Foundation of China(Grant No.22075163).
文摘Carbon nanotubes have attracted extensive interest owing to their extraordinary properties and wide applications in many fields.Among various types of carbon nanotubes,only ultralong carbon nanotubes with macroscale lengths,low defect concentrations,and high degrees of alignment can fully demonstrate their intrinsic performance.These attributes make ultralong carbon nanotubes highly promising for applications in cutting-edge fields,such as carbon-based integrated circuits,ultra-strong fibers,and transparent conductive films.However,the mass production of ultralong carbon nanotubes with precise structural control remains a major challenge,limiting their widespread applications.In the past decades,great progress has been achieved in the study of ultralong carbon nanotubes.In this review,we summarized the growth mechanisms and the controlled synthesis strategies of ultralong carbon nanotubes.Then,we introduced the advanced applications of ultralong carbon nanotubes in many areas,such as field-effect transistors,sensors,and photodetectors.Finally,we discussed the remaining challenges and offered our perspectives on the future directions of this field.
基金supported by the National Key R&D Plan of China(2022YFB3603800 and 2020YFB0204802)the National Natural Science Foundation of China(T2225028 and 22075295)+2 种基金Chinese Academy of Sciences(Hundred Talents PlanYouth Innovation Promotion Association,Young Scientists in Basic Research(YSBR-053))the Strategic Priority Research Program of Science(XDB0520201).
文摘Emerging monolayer molecular crystals(MMCs)have become prosperous in recent decades due to their numerous advantages.First,downsizing the active layer thickness to monolayer in organic field-effect transistors(OFETs)is beneficial to elucidate the intrinsic charge-transport behavior.Next,the ultrathin conducting channel can reduce bulk injection resistance to extract mobility accurately.Then,direct exposure of the conducting channel can enhance the sensing performance.Finally,MMCs combine the merits of ultrathin thickness and high crystallization,which will improve the optoelectronic performance and realize complex device architectures for future advanced optoelectronic applications.In this Review,recent research progress in precise preparations and advanced applications of solution-processed MMCs are summarized.We present the current challenges related to MMCs with specific structures and desired performances,and an outlook regarding their application in next-generation integrated organic optoelectronics is provided.
基金financially supported by the National Natural Science Foundation of China(No.52073208)the China Postdoctoral Science Foundation(No.2022M722356)+1 种基金Seed Foundation of Tianjin University(Nos.2023XQM-0028 and 2023XSU-0020)the Fundamental Research Funds for the Central Universities.
文摘Covalent organic framework(COF)monolayers,with atomically thin,ordered networks,and rich functionality,are widely studied due to their unusual structure/property relationships.However,synthesizing COF monolayer has remained an unmet challenge due to the difficulty of controlling reactions at the monolayer limit with large-scale uniformity.The identification and development of new reactions and polymerization conditions are critical for the further advancement of COF monolayer materials.Moreover,as one-molecule-thick a freestanding films,COF monolayer offers an ideal material system.Many advanced applications of COF monolayer have been explored in recent literature.This review provides an overview of the current state of precise synthetic strategies for COF monolayer,highlighting the advantages and limitations of different synthetic approaches and key challenges related to enhancing quality,and emphasizing the unique benefits of COF monolayer as both an ideal model system and for advanced applications.
基金supported by the National Natural Science Foundation of China(Grant Nos.22005115,21932003,and 22161132009).
文摘Hydrogels,which are three-dimensional networks of crosslinked hydrophilic polymers,have become crucial for various advanced applications owing to their exceptional water absorption and swelling properties.This review explores the applications of hydrogels based on their unique swelling properties,beyond their application in traditional drug delivery,focusing on atmospheric water harvesting,hydrogel actuator,expansion microscopy(ExM),and 3D nanofabrication through controlled deswelling.We first discuss the factors influencing hydrogel swelling,such as network size and polymer properties.Next,we explore the mechanisms underlying hydrogel swelling,emphasizing the interplay between various forces.Hydrogel swelling enables ExM for super-resolution imaging of biological tissues,while controlled deswelling of hydrogels facilitates the creation of intricate 3D structures with nanoscale precision—a breakthrough for additive manufacturing techniques.Despite these advantages,challenges still remain.We conclude this review by emphasizing the need for interdisciplinary research to address these limitations and unlock the full potential of the hydrogel technology.The future of hydrogel research holds promise for revolutionary contributions to environmental science,robotics,and biomedical imaging.
文摘This paper presents a review of the position-sensitive detector(PSD) sensor, covering different types of PSD and recent works related to this field. Furthermore, it explains the theoretical concepts and provides information about its structure and principles of operation. Moreover, it includes the main information about the available commercial PSDs from different companies, along with a comparison between the common modules. The PSD features include high position resolution, fast response, and a wide dynamic range. These features make it suitable for various fields and applications, such as imaging, spectrometry, spectroscopy and others.
文摘Facility management and maintenance of the Thermal-Energy-Storage Air-Conditioning(TES-AC)system is a tedious task at a large scale mainly due to the charging load that can increase energy consumption if needed to be charged at peak hours.Besides,maintenance of TES-AC at a large scale gets complex as it contains many sensor data.By utilizing deep learning techniques on the sensor data,charging load prediction can be made possible,so facility managers can prepare in advance.However,a deep learning-based application will be unusable if it is not deployed in a user-friendly manner where facility managers can benefit from this application.Hence,this research focuses on gathering design guidelines for a deep learning-based application and further validates the design considerations with a developed application for efficient human-computer interaction through qualitative analysis.The approach taken to gather design guidelines demonstrated a positive correlation between expert-suggested features and the user-friendly aspect of the application as 67.08%of participants found the features suggested by experts to be most satisfactory.Furthermore,it evaluates user satisfaction with the advanced developed application for TES-AC according to the gathered design guidelines.
基金Supported by National Natural Science Foundation of China(Grant No.51575150)
文摘The theoretical research of cable-driven mechanisms is developed with its broad applications. The first prototype of cable-driven mechanisms is RoboCrane, which was developed by the National Institute of Standards and Technology （NIST）. Then many excellent properties were developed and they have a variety of applications such as aerospace, aircraft and automobile industries [1]. Example application for RoboCrane in the field of aircraft mainte- nance is equipped with a quick-change mechanism to remove the robot arm remotely.
文摘The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising with increasing frequency in widely different areas, which cannot be addressed using conventional control techniques. The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where presence of large uncertainties as well as nonlinearities plays a major role. For instance, the design of unmanned aircraft, unmanned underwater vehicles, and automatic driving systems for automobiles are all typical examples of such difficult control problems. The large uncertainties concerning the plant may arise due to large external disturbances, large parameter variations because of faults in the system, or failure of some of the subsystems. In such cases, the controller has to determine the specific situation that exists at any instant, and take the appropriate control action. Accomplishing this rapidly, accurately, and in a stable fashion is the objective of control design.
文摘Computational seismology is a relatively new interdisciplinary field spanning computational techniques in theoretical and observational seismology. It studies numerical methods and their implementation in various theoretical and applied problems in seismology.
基金supported by the National Natural Science Foun-dation of China(52476020)the National Key Research and Devel-opment Program of China(2023YFF0721304)the“Pioneer”and“Leading Goose”Research and Development Program of Zhe-jiang Province,China(2025C01080).
文摘Pulse tube cryocoolers working at liquid helium temperatures(LHe-PTCs),particularly those in a separated configuration-where the rotary valve assembly is positioned remotely from the cold head-exhibit high reliability,long service life,low vibration,and strong resistance to electromagnetic interference.These characteristics make them indispensable for cryogen-free systems.Separated LHe-PTCs are widely used in advanced applications such as quantum physics[1]and particle physics[2],serving as core components in instruments including dilution refrigerators,scanning tunneling microscopes(STM),and superconducting magnet systems.
基金This manuscript was authored in part by UT-Battelle LLC under contract DE-AC05-00OR22725 with DOE.
文摘Considering the growing concerns about natural resource depletion,energy inequality,and climate crises,biomassderived materials—the most abundant organic matter on the planet—have received a lot of attention as a potential alternative to petroleum-based plastics.Herbaceous biomasses and extracted cellulose have recently been extensively used in the development of high-performance and multifunctional materials.Herbaceous biomass has sparked interest due to its species diversity,abundance,low cost,lightweight,and sustainability.This review discusses the structure versus property relationships of various sources of herbaceous biomasses(e.g.,sugarcane,straw,and bamboo)and their extracted biomaterials,as well as the latest emerging applications from macro-and microscales to nanoscales.High-strength structural materials,porous carbon materials,multichannel materials,and flexible materials are examples of these applications,which include sustainable electronics,environmentally friendly energy harvesting,smart materials,and biodegradable structural buildings.
基金State Key Program of National Natural Science Foundation of China,Grant/Award Number:52130303National Natural Science Foundation of China,Grant/Award Number:51773147。
文摘In the wave of the Internet era created by computer and communication technology,flexible sensors play an important role in accurately collecting information owing to their excellent flexibility,ductility,freeform bending or folding,and versatile structural shapes.By endowing elastomeric polymers with conductivity,researchers have recently devoted extensive efforts toward developing high-performance flexible sensors based on elastomeric conductive layers and exploring their potential applications in diverse fields ranging from project manufacturing to daily life.This review reports the recent advancements in elastomeric polymers used to make conductive layers,as well as the relationships between elastomeric polymers and the performance and application of flexible sensors are comprehensively summarized.First,the principles and methods for using elastomeric polymers to construct conductive layers are provided.Then,the fundamental design,unique properties,and underlying mechanisms in different flexible sensors(pressure/strain,temperature,humidity)and their related applications are revealed.Finally,this review concludes with a perspective on the challenges and future directions of high-performance flexible sensors.
基金support from the National Natural Science Foundation of China(Grant Nos.52425308,62374035 and 92263106).
文摘CONSPECTUS:Ultraviolet(UV)light,spanning wavelengths from 10 to 400 nm,is ubiquitous in military,livelihood,and scientific domains.Accurate UV photodetection is therefore essential for monitoring environmental radiation,safeguarding human health,and advancing technological applications in fields such as aerospace,medical science,and ecology.The fabrication of high-performance UV photodetection devices fundamentally depends on the development of high-sensitivity UV photosensitive materials.The evolution of UV photodetection materials has progressed from early wide-bandgap semiconductors like ZnS and ZnSe to third-generation semiconductors such as GaN and Ga_(2)O_(3),and most recently to two-dimensional(2D)wide-bandgap materials that combine exceptional optoelectronic properties with compelling physicochemical properties.Among these,2D perovskite oxides stand out due to their prominent advantages for UV detection.First,this large family of materials generally features wide bandgaps,strong UV absorption,and high spectral selectivity.Second,the tunable bandgaps of 2D perovskite oxides enable precise detection at specific wavelengths.Third,their excellent processability and flexibility facilitate feasible integration into devices,making them promising candidates for flexible photodetectors.Furthermore,2D perovskite oxides boast other properties such as high stability,dielectricity,ferroelectricity,and biocompatibility.These characteristics have promoted the blossoming of 2D perovskite oxides for highperformance UV photodetection and are poised to expand their applications in novel functional optoelectronics.In this Account,we systematically review the development of 2D perovskite oxides,with a focus on their application in the fabrication of high-performance UV photodetectors.First,we describe the top-down synthesis of these materials,highlighting key advances in synthesis techniques.Second,we specifically analyze the intrinsic advantages of 2D perovskite oxides which render them highly suitable for UV detection.Third,we discuss recent progress in the fabrication of UV photodetectors based on 2D perovskite oxides,emphasizing effective strategies for achieving high-performance devices.Next,we explore state-of-the-art optoelectronic applications leveraging these materials.Finally,we present our perspectives on the future development of this promising class of UVsensitive materials.Given their remarkable material diversity,we believe that this Account will provide valuable insights to guide future research and the application of 2D perovskite oxides in high-performance UV photodetectors and functional optoelectronics.
文摘Electron-induced colour routers actively manipulate dichromatic photon momentum at deep subwavelength scales,enabling programmable encrypted displays with enhanced security and high integration for advanced photonic applications.
文摘Transmission loss of holey fiber is found to depend on its structure, and to be caused by Rayleigh scattering at glass surface. Under this loss dependence, most promising is optical wiring application, for which fiber designs to realize bend-insensitivity and single-modedness are presented.
基金supported by the Guangdong Key Research and Development Program(No.2018B090904001)the National Natural Science Foundations of China(Nos.62005313 and 61705264)+1 种基金the Innovative Research Team in Natural Science Foundation of Hunan Province(No.2019JJ10005)the Hunan Provincial Innovation Construct Project(No.2019RS3017)。
文摘In this paper,an all-fiberized and narrow-linewidth 5 kW power-level fiber amplifier is presented.The laser is achieved based on the master oscillator power amplification configuration,in which the phase-modulated single-frequency laser is applied as the seed laser and a bidirectional pumping configuration is applied in the power amplifier.The stimulated Brillouin scattering,stimulated Raman scattering,and transverse mode instability effects are all effectively suppressed in the experiment.Consequently,the output power is scaled up to 4.92 kW with a slope efficiency of as high as approximately 80%.The 3-dB spectral width is about 0.59 nm,and the beam quality is measured to be M^(2)~1.22 at maximum output power.Furthermore,we have also conducted a detailed spectral analysis on the spectral width of the signal laser,which reveals that the spectral wing broadening phenomenon could lead to the obvious decrease of the spectral purity at certain output power.Overall,this work could provide a reference for obtaining and optimizing high-power narrow-linewidth fiber lasers.
基金supported by the U.S. Department of Energy Accelerator Stewardship programme, Office of High Energy Physics, Office of Science under award DE-SC0016136support by the U.S. Department of Energy, Office of Science SBIR programme under award DE-SC0011375
文摘Recent results in the development of diode-driven high energy, high repetition rate, picosecond lasers, including the demonstration of a cryogenic Yb:YAG active mirror amplifier that produces 1.5 J pulses at 500 Hz repetition rate(0.75 kW average power) are reviewed. These pulses are compressed resulting in the generation of ~5 ps duration,1 J pulses with 0.5 kW average power. A full characterization of this high power cryogenic amplifier, including atwavelength interferometry of the active region under >1 kW average power pump conditions, is presented. An initial demonstration of operation at 1 kW average power(1 J, 1 k Hz) is reported.
基金partially supported by grant DE130100205 from the Australian Research Council
文摘The increasing demana for advanced modelling methods, which can reflect complex travel activities of individuals, requires enhanced travel data collection methods. The introduction of GPS-assisted data collection methods has provided an alternative to the conventional methods of travel data collection. GPS-assisted data collection methods improve the accu- racy of data collection and enable capturing more details of individuals＇ travel behaviour. Recent technological advancements in smartphone-based positioning technologies and communication facilities have opened up new opportunities to apply smartphones as the media of GPS-assisted data collection. Although, different GPS-assisted methods have been employed recently, their performance has not been widely evaluated in real-world experi- ments compared to traditional data collection methods. Accordingly, this paper evaluates the performance of three GPS-assisted methods, namely handheld GPS tracking, smart- phone-based GPS tracking and smartphone-based prompted-recall data collection methods, in conjunction with the web-based data collection to shed light on different aspects of GPS- assisted data collection methods. These methods are compared in terms of the quality and accuracy of the collected data, the demographic attributes of participants and the specifi- cations of labelled trips. The results show that an appropriate employment of smartphones enhances the accuracy of data collection. It is also found that putting an extra burden on participants during a travel data collection survey results in lower trip-rates and poor data quality. Finally, it is found that the application of smartphone-assisted data collection methods help reporting non-motorised trips more accurately.
