Micro/nanoscale robots(MNRs)have attracted significant interest in various fields because of their flexible design,physically controlled maneuvering,and barrier targeting.The execution of specific functions using MNRs...Micro/nanoscale robots(MNRs)have attracted significant interest in various fields because of their flexible design,physically controlled maneuvering,and barrier targeting.The execution of specific functions using MNRs relies on precise propulsion methods.Among the diverse propulsion techniques,physical propulsion is widely used owing to its noninvasive,safe,and convenient attributes.This review provides an analysis of the propulsion mechanisms in the magnetic,electric,thermal,and ultrasound fields and presents a comprehensive summary of the structures,movements,and applications of various MNRs while also examining their advantages and shortcomings associated with various physical propulsion methods.Finally,challenges and perspectives associated with the future development of MNRs are presented.The content of this review can serve as a multidisciplinary science reference for physicists,bioengineers,clinicians,roboticists,and chemists involved in pharmaceutical design and clinical therapy research.展开更多
Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical in...Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical interactions of additives with the perovskite lattice,band structure,and charge carriers.Herein,how additives of cellulose triacetate(CTA)improve the photovoltaic performance and stability of perovskite solar cells(PSCs)is shown.These improvements are found to stem from the formation of hydrogen bonds between CTA molecules and organic cations.The Kelvin probe force microscopy results show that contact potential difference variation under dark and light conditions increases from 79.68 to 141.24 mV by doping CTA,indicating enhanced separation of electron-hole pairs in perovskite.The piezoresponse force microscopy(PFM)tests indicate that CTA additives reduce the PFM amplitude by approximately 50 pm under dark and light conditions and inhibit flipping from antiferroelectric domains to ferroelectric domains.Moreover,the CTA additives regulate the charge distribution within the PbI6 octahedron and bind organic ions through hydrogen bonding,forming a compact film structure.These findings not only improve the long-term stability of organic-inorganic hybrid perovskites(OIHPs),but also pave the way for developing novel strategies for large-scale PSCs.展开更多
Friction and wear are unavoidable in mechanical movement.The use of lubricants with nano-additives can effectively reduce friction and wear,which is of great significance to saving energy and protecting the environmen...Friction and wear are unavoidable in mechanical movement.The use of lubricants with nano-additives can effectively reduce friction and wear,which is of great significance to saving energy and protecting the environment.At present,great progress has been made in the scientific research and industrial application of nano-additives for lubricants.This paper mainly introduces the types of nano-additives for lubricants(such as carbon nanomaterials,nano-metals,nano-oxides,sulfides,complexes,polymers,etc.),the tribological properties of lubricants with different components of nano-additives,and the lubrication mechanisms of the nano-additives(including tribofilm formation,rolling ball bearing effect,repairing effect,polishing effect,and synergistic effect).It also deals with the dispersion of nano-additives in lubricants and the influences of their particle size and microstructure on the tribological properties of lubricants.This review outlines the performance requirements of nano-additives in different lubrication states,discusses the use of nano-additives in challenging working conditions,and identifies various industrial oil nano-additives with reference to the appropriate options in diverse working environments.Furthermore,the existing problems of nano-additives and their application prospects are summarized.This review,hopefully,would help to shed light on the design and synthesis of novel high-performance nano-additives and promote their application in engineering.展开更多
Structure manipulation of photocatalysts at an atomic scale is a promising way to improve its photocatalytic performance.Herein,we realize the anchoring of single Ni atoms on the ZnIn_(2)S_(4) nanosheets with rich sul...Structure manipulation of photocatalysts at an atomic scale is a promising way to improve its photocatalytic performance.Herein,we realize the anchoring of single Ni atoms on the ZnIn_(2)S_(4) nanosheets with rich sulfur vacancies.Experimental results demonstrate that single Ni atoms induce the formation of NiO-M(Zn/In) atomic interface,which can efficiently promote the carriers separation and prolong the carrier life time.In addition,in situ electron spin resonance spectroscopy(ESR) confirms that the single Ni atoms act as an electron trapping center for protons reduction.As a result,the single Ni atoms decorated ZnIn_(2)S_(4) nanosheets with rich sulfur vacancies(Ni/ZnIn_(2)S_(4)-RVs) shows a hydrogen evolution rate up to 89.4 μmol h^(-1), almost 5.7 and 2.3 times higher compared to that of ZnIn_(2)S_(4) nanosheets with poor sulfur vacancies and rich sulfur vacancies(denoted as ZnIn_(2)S_(4)-PVs and ZnIn_(2)S_(4)-RVs).This work opens up a new perspective manipulating the single-atom cocatalyst and sulfur vacancy on sulfide supports for improving photocatalytic hydrogen evolution.展开更多
During the past several years, giant magneto-impedance effect (GMI) in amorphous wires has generated growing interest in the science community because of their applications in sensors. The giant magneto-impedance effe...During the past several years, giant magneto-impedance effect (GMI) in amorphous wires has generated growing interest in the science community because of their applications in sensors. The giant magneto-impedance effect in Co71.8Fe4.9Nb0.8Si7.5B15 amorphous glass-covered wires (AGCW) consists of strong changes in the high frequency impedance with a small DC magnetic field. When f=1 MHz, there is no GMI effect due to the fact that the magnetic penetration depth is higher than their radius. As the frequency increases, the GMI effect becomes important in both the glass-covered wire and the wire after glass removal. Field dependence of the impedance has a similar behaviour to the AGCW ones, when a tensile stress is applied to the wire without glass cover.展开更多
The giant stress-impedance(GSI)effect in as-cast and DC current annealed Co71.8Fe4.9 Nb0.8Si7.5 B15 amorphous glass-covered wires is presented.The SI ratio of the as-cast sample exhibits negative GSI effect.For the sa...The giant stress-impedance(GSI)effect in as-cast and DC current annealed Co71.8Fe4.9 Nb0.8Si7.5 B15 amorphous glass-covered wires is presented.The SI ratio of the as-cast sample exhibits negative GSI effect.For the sample annealed by 60 mA DC current,the SI ratio first increases with applied tensile stress,then decreases.The maximumΔZ/Z ratio of 304%is obtained.Frequency dependence in the range from 1 to 110 MHz of the GSI effect is investigated.Experimental results show that the real part R and the imaginary part X of impedance play an important role at high frequency and low frequency,respectively.At 1 MHz,the maximum AX/X ratio of 1448%is obtained.At 110 MHz,the maximum AR/R ratio of 648%is obtained.展开更多
The Co_(71.8)Fe_(4.9)Nb_(0.8)Si_(7.5)B_(15)amorphous glass-covered wires(AGCW)are prepared by the Taylor-Ulitovsky technique.The frequency dependence of asymmetrical giant magneto-impedance(AGMI)effect in amorphous gl...The Co_(71.8)Fe_(4.9)Nb_(0.8)Si_(7.5)B_(15)amorphous glass-covered wires(AGCW)are prepared by the Taylor-Ulitovsky technique.The frequency dependence of asymmetrical giant magneto-impedance(AGMI)effect in amorphous glass-covered wires annealed by 70 mA DC current is here presented.The resistance R and the reactance X have been measured,respectively.The real part R and the imaginary part X of impedance play an important role at high frequency and low frequency,respectively.The influence of DC bias current from I_(b)=0 mA to I_(b)=5 mA at 30 MHz on the GMI effect in the glass-covered wires annealed by 70 mA DC current is investigated.The asymmetry becomes the largest around I_(b)=1 mA,and finally decreases for the larger bias current I_(b)=5 mA.The maximumΔZ/Z ratio of 310%is observed at 58 MHz under 1 mA bias current.展开更多
To obtain the optimal operating conditions of a coupled reactor for pyridine synthesis,reactor modeling process is carried out in this paper.During the modeling process,the flow hydrodynamics,heat transfer behavior,in...To obtain the optimal operating conditions of a coupled reactor for pyridine synthesis,reactor modeling process is carried out in this paper.During the modeling process,the flow hydrodynamics,heat transfer behavior,inter-phase mass transfer behavior and reaction kinetics were taken into consideration consequently.Further,a regression program based on least square method was proposed to regress the model parameters.The prediction results agreed well with the experimental results with an average deviation of 5.9%.Finally,by setting suitable aim function,the optimal operating conditions of the coupled reactor for pyridine synthesis were determined.展开更多
A material-structure integrated design method is proposed in this paper,with which micropillar and microwedge arrayed surfaces are fabricated based on a novel nanoparticlereinforced silicone rubber composite(NRSRC)wit...A material-structure integrated design method is proposed in this paper,with which micropillar and microwedge arrayed surfaces are fabricated based on a novel nanoparticlereinforced silicone rubber composite(NRSRC)with high mechanical strength and strong surface adhesion.It is found that the micropillar-arrayed surface and the microwedgearrayed surface show a normal adhesive strength of 50.9 kPa and a shear adhesive strength of 137.3 kPa,respectively,which are much higher than those of previously reported adhesive surfaces made by pure soft polymers.Furthermore,the micro-wedgearrayed surface shows not only strong and stable adhe-sion on rough and smooth substrates but also an obvious anisotropy in the adhesion property.The latter consequently leads to an easy control of the attachment/detachment switch,which is evidenced by a mechanical gripper with a microwedged surface.Therefore,firmly picking up and easily releasing a heavy glass plate can be realized.All these results demonstrate the apparent advantages of the present compo-sitebased fibrillar surfaces in achieving reliable and reversible adhesion and should have promising applications for manufac-turing advanced adhesive devices,such as mechanical fixtures,portable climbing equipment and space robots.展开更多
基金the National Natural Science Foundation of China(Nos.U2130128 and 12102376)Yanzhao Young Scientist Project from Natural Science Foundation of Hebei Province(No.B2023205040)+6 种基金Basic Research Cooperation Special Foundation of Beijing-Tianjin-Hebei Region(Nos.H2022205047,22JCZXJC00060,and E3B33911DF)Central Government Guiding Local Science and Technology Development Project(No.216Z4302G)Hebei Administration for Market Supervision Science and Technology Project List(No.2023ZC03)Innovation Capability Improvement Plan Project of Hebei Province(No.22567604H)Ph.D Scientific Research Start-up Fund(No.L2023B18)College Student’s Innovation and Entrepreneurship Training Plan Program(No.S202410094046)of Hebei Normal Universitythe Guangdong Basic and Applied Basic Research Foundation(No.2023A1515011592).
文摘Micro/nanoscale robots(MNRs)have attracted significant interest in various fields because of their flexible design,physically controlled maneuvering,and barrier targeting.The execution of specific functions using MNRs relies on precise propulsion methods.Among the diverse propulsion techniques,physical propulsion is widely used owing to its noninvasive,safe,and convenient attributes.This review provides an analysis of the propulsion mechanisms in the magnetic,electric,thermal,and ultrasound fields and presents a comprehensive summary of the structures,movements,and applications of various MNRs while also examining their advantages and shortcomings associated with various physical propulsion methods.Finally,challenges and perspectives associated with the future development of MNRs are presented.The content of this review can serve as a multidisciplinary science reference for physicists,bioengineers,clinicians,roboticists,and chemists involved in pharmaceutical design and clinical therapy research.
基金supported by the National Natural Science Foundation of China(No.U2130128)Yanzhao Young Scientist Project from Natural Science Foundation of Hebei Province(Nos.B2023205040)+4 种基金Basic Research Cooperation Special Foundation of Beijing-Tianjin-Hebei Region(Nos.H2022205047,22JCZXJC00060 and E3B33911DF)Hebei Administration for Market Supervision Science and Technology Project List(No.2023ZC03)the Innovation Capability Improvement Plan Project of Hebei Province(No.22567604H)Ph.D.Scientific Research Start-up Fund of Hebei Normal University(No.L2023B18)College Student’s Innovation and Entrepreneurship Training Plan Program(No.S202410094046).
文摘Additive engineering significantly enhances the photovoltaic performance of perovskite solar cells(PSCs).The atomistic and mechanistic origins of these jfurther investigation to fully understand the physicochemical interactions of additives with the perovskite lattice,band structure,and charge carriers.Herein,how additives of cellulose triacetate(CTA)improve the photovoltaic performance and stability of perovskite solar cells(PSCs)is shown.These improvements are found to stem from the formation of hydrogen bonds between CTA molecules and organic cations.The Kelvin probe force microscopy results show that contact potential difference variation under dark and light conditions increases from 79.68 to 141.24 mV by doping CTA,indicating enhanced separation of electron-hole pairs in perovskite.The piezoresponse force microscopy(PFM)tests indicate that CTA additives reduce the PFM amplitude by approximately 50 pm under dark and light conditions and inhibit flipping from antiferroelectric domains to ferroelectric domains.Moreover,the CTA additives regulate the charge distribution within the PbI6 octahedron and bind organic ions through hydrogen bonding,forming a compact film structure.These findings not only improve the long-term stability of organic-inorganic hybrid perovskites(OIHPs),but also pave the way for developing novel strategies for large-scale PSCs.
基金National Natural Science Foundation of China(21805085)The Key Technologies R&D Program of Henan Province(212102210039)+2 种基金Scientific and Technological Innovation Team of Henan Province University(22IRTSTHN018)Zhongyuan Science and Technology Innovation Leadership Program(214200510024)Visiting Professor Fund Project of North China University of Water Resources and Electric Power(4001-40734).
文摘Friction and wear are unavoidable in mechanical movement.The use of lubricants with nano-additives can effectively reduce friction and wear,which is of great significance to saving energy and protecting the environment.At present,great progress has been made in the scientific research and industrial application of nano-additives for lubricants.This paper mainly introduces the types of nano-additives for lubricants(such as carbon nanomaterials,nano-metals,nano-oxides,sulfides,complexes,polymers,etc.),the tribological properties of lubricants with different components of nano-additives,and the lubrication mechanisms of the nano-additives(including tribofilm formation,rolling ball bearing effect,repairing effect,polishing effect,and synergistic effect).It also deals with the dispersion of nano-additives in lubricants and the influences of their particle size and microstructure on the tribological properties of lubricants.This review outlines the performance requirements of nano-additives in different lubrication states,discusses the use of nano-additives in challenging working conditions,and identifies various industrial oil nano-additives with reference to the appropriate options in diverse working environments.Furthermore,the existing problems of nano-additives and their application prospects are summarized.This review,hopefully,would help to shed light on the design and synthesis of novel high-performance nano-additives and promote their application in engineering.
基金the support of the National Natural Science Foundation of China(51702087,21673066)the Project funded by the China Postdoctoral Science Foundation(2019M652516)。
文摘Structure manipulation of photocatalysts at an atomic scale is a promising way to improve its photocatalytic performance.Herein,we realize the anchoring of single Ni atoms on the ZnIn_(2)S_(4) nanosheets with rich sulfur vacancies.Experimental results demonstrate that single Ni atoms induce the formation of NiO-M(Zn/In) atomic interface,which can efficiently promote the carriers separation and prolong the carrier life time.In addition,in situ electron spin resonance spectroscopy(ESR) confirms that the single Ni atoms act as an electron trapping center for protons reduction.As a result,the single Ni atoms decorated ZnIn_(2)S_(4) nanosheets with rich sulfur vacancies(Ni/ZnIn_(2)S_(4)-RVs) shows a hydrogen evolution rate up to 89.4 μmol h^(-1), almost 5.7 and 2.3 times higher compared to that of ZnIn_(2)S_(4) nanosheets with poor sulfur vacancies and rich sulfur vacancies(denoted as ZnIn_(2)S_(4)-PVs and ZnIn_(2)S_(4)-RVs).This work opens up a new perspective manipulating the single-atom cocatalyst and sulfur vacancy on sulfide supports for improving photocatalytic hydrogen evolution.
基金This work was financially supported by the National High-Tech Research and Development Program (No. 2002AA302601) and the National Key Technologies Research and Development Program (No. 2004BA310A51).
文摘During the past several years, giant magneto-impedance effect (GMI) in amorphous wires has generated growing interest in the science community because of their applications in sensors. The giant magneto-impedance effect in Co71.8Fe4.9Nb0.8Si7.5B15 amorphous glass-covered wires (AGCW) consists of strong changes in the high frequency impedance with a small DC magnetic field. When f=1 MHz, there is no GMI effect due to the fact that the magnetic penetration depth is higher than their radius. As the frequency increases, the GMI effect becomes important in both the glass-covered wire and the wire after glass removal. Field dependence of the impedance has a similar behaviour to the AGCW ones, when a tensile stress is applied to the wire without glass cover.
基金Item Sponsored by National High Tech Research and Development Program(2002AA302601)National Key Technologies Research and Development Program(2004BA310A51).
文摘The giant stress-impedance(GSI)effect in as-cast and DC current annealed Co71.8Fe4.9 Nb0.8Si7.5 B15 amorphous glass-covered wires is presented.The SI ratio of the as-cast sample exhibits negative GSI effect.For the sample annealed by 60 mA DC current,the SI ratio first increases with applied tensile stress,then decreases.The maximumΔZ/Z ratio of 304%is obtained.Frequency dependence in the range from 1 to 110 MHz of the GSI effect is investigated.Experimental results show that the real part R and the imaginary part X of impedance play an important role at high frequency and low frequency,respectively.At 1 MHz,the maximum AX/X ratio of 1448%is obtained.At 110 MHz,the maximum AR/R ratio of 648%is obtained.
基金Sponsored by the National High-Tech Research and Development Program of China(2002AA302601)the National Key Technologies Research and Development Programof China(2004BA310A51)
文摘The Co_(71.8)Fe_(4.9)Nb_(0.8)Si_(7.5)B_(15)amorphous glass-covered wires(AGCW)are prepared by the Taylor-Ulitovsky technique.The frequency dependence of asymmetrical giant magneto-impedance(AGMI)effect in amorphous glass-covered wires annealed by 70 mA DC current is here presented.The resistance R and the reactance X have been measured,respectively.The real part R and the imaginary part X of impedance play an important role at high frequency and low frequency,respectively.The influence of DC bias current from I_(b)=0 mA to I_(b)=5 mA at 30 MHz on the GMI effect in the glass-covered wires annealed by 70 mA DC current is investigated.The asymmetry becomes the largest around I_(b)=1 mA,and finally decreases for the larger bias current I_(b)=5 mA.The maximumΔZ/Z ratio of 310%is observed at 58 MHz under 1 mA bias current.
基金supports from the Natural Science Foundation of Henan(grant No.202300410063)the National Natural Science Foundation of China(grant Nos.91834303,21961132026)+1 种基金the First-class Discipline Construction Project of Henan University(grant No.2019YLZDCG01)the interdisciplinary Research for First-class Discipline Construction Project of Henan University(grant No.2019 YLXKJC04).
文摘To obtain the optimal operating conditions of a coupled reactor for pyridine synthesis,reactor modeling process is carried out in this paper.During the modeling process,the flow hydrodynamics,heat transfer behavior,inter-phase mass transfer behavior and reaction kinetics were taken into consideration consequently.Further,a regression program based on least square method was proposed to regress the model parameters.The prediction results agreed well with the experimental results with an average deviation of 5.9%.Finally,by setting suitable aim function,the optimal operating conditions of the coupled reactor for pyridine synthesis were determined.
基金NSFC through Grants(No.12032004,No.12293000,No.12293002,No.12272043)Natural Science Foundation of Henan(No.202300410088)as well as Innovation Demonstration Project of Henan(No.201111211400).
文摘A material-structure integrated design method is proposed in this paper,with which micropillar and microwedge arrayed surfaces are fabricated based on a novel nanoparticlereinforced silicone rubber composite(NRSRC)with high mechanical strength and strong surface adhesion.It is found that the micropillar-arrayed surface and the microwedgearrayed surface show a normal adhesive strength of 50.9 kPa and a shear adhesive strength of 137.3 kPa,respectively,which are much higher than those of previously reported adhesive surfaces made by pure soft polymers.Furthermore,the micro-wedgearrayed surface shows not only strong and stable adhe-sion on rough and smooth substrates but also an obvious anisotropy in the adhesion property.The latter consequently leads to an easy control of the attachment/detachment switch,which is evidenced by a mechanical gripper with a microwedged surface.Therefore,firmly picking up and easily releasing a heavy glass plate can be realized.All these results demonstrate the apparent advantages of the present compo-sitebased fibrillar surfaces in achieving reliable and reversible adhesion and should have promising applications for manufac-turing advanced adhesive devices,such as mechanical fixtures,portable climbing equipment and space robots.
