This paper designs and implements a single-camera 360°panoramic imaging system based on motor-driven fisheye rotation.The system utilizes a stepper motor for precise angular control,enabling the camera to rotate ...This paper designs and implements a single-camera 360°panoramic imaging system based on motor-driven fisheye rotation.The system utilizes a stepper motor for precise angular control,enabling the camera to rotate around its optical center to capture multi-view images,thereby avoiding the parallax and geometric mismatch problems inherent in traditional multi-camera configurations.To address the strong distortion characteristics of fisheye images,an equidistant projection model is adopted for distortion correction.On this basis,a brightness normalization method combining global linear brightness correction and local illumination compensation is proposed to enhance stitching consistency.By establishing a geometry model constrained by camera rotation and integrating cylindrical projection with cosine-weighted blending,the system achieves high-precision panoramic stitching and seamless visual transitions.展开更多
With the advent of the digital economy,there has been a rapid proliferation of small-scale Internet data centers(SIDCs).By leveraging their spatiotemporal load regulation potential through data workload balancing,aggr...With the advent of the digital economy,there has been a rapid proliferation of small-scale Internet data centers(SIDCs).By leveraging their spatiotemporal load regulation potential through data workload balancing,aggregated SIDCs have emerged as promising demand response(DR)resources for future power distribution systems.This paper presents an innovative framework for assessing capacity value(CV)by aggregating SIDCs participating in DR programs(SIDC-DR).Initially,we delineate the concept of CV tailored for aggregated SIDC scenarios and establish a metric for the assessment.Considering the effects of the data load dynamics,equipment constraints,and user behavior,we developed a sophisticated DR model for aggregated SIDCs using a data network aggregation method.Unlike existing studies,the proposed model captures the uncertainties associated with end tenant decisions to opt into an SIDC-DR program by utilizing a novel uncertainty modeling approach called Z-number formulation.This approach accounts for both the uncertainty in user participation intentions and the reliability of basic information during the DR process,enabling high-resolution profiling of the SIDC-DR potential in the CV evaluation.Simulation results from numerical studies conducted on a modified IEEE-33 node distribution system confirmed the effectiveness of the proposed approach and highlighted the potential benefits of SIDC-DR utilization in the efficient operation of future power systems.展开更多
As the cornerstone of sterile instrument maintenance in endoscopy centers,the quality of endoscope cleaning directly impacts hospital infection control effectiveness.The traceability system for endoscopy centers utili...As the cornerstone of sterile instrument maintenance in endoscopy centers,the quality of endoscope cleaning directly impacts hospital infection control effectiveness.The traceability system for endoscopy centers utilizes digital means to document the entire cleaning process,enabling real-time monitoring and precise quality control.This paper analyzes current quality control practices in endoscope cleaning and addresses existing challenges.It explores how traceability systems standardize procedures,enhance monitoring,and improve management efficiency.The study proposes optimization strategies for traceability system implementation,clarifying its core value in endoscope cleaning quality control.These findings provide theoretical foundations and practical guidance for hospitals to refine management of endoscopy centers,ensure diagnostic safety,and reduce infection risks,ultimately advancing endoscope cleaning quality control toward standardized and informatized development.展开更多
Rack-level loop thermosyphons have been widely adopted as a solution to data centers’growing energy demands.While numerous studies have highlighted the heat transfer performance and energy-saving benefits of this sys...Rack-level loop thermosyphons have been widely adopted as a solution to data centers’growing energy demands.While numerous studies have highlighted the heat transfer performance and energy-saving benefits of this system,its economic feasibility,water usage effectiveness(WUE),and carbon usage effectiveness(CUE)remain underexplored.This study introduces a comprehensive evaluation index designed to assess the applicability of the rack-level loop thermosyphon system across various computing hub nodes.The air wet bulb temperature Ta,w was identified as the most significant factor influencing the variability in the combination of PUE,CUE,and WUE values.The results indicate that the rack-level loop thermosyphon system achieves the highest score in Lanzhou(94.485)and the lowest in Beijing(89.261)based on the comprehensive evaluation index.The overall ranking of cities according to the comprehensive evaluation score is as follows:Gansu hub(Lanzhou)>Inner Mongolia hub(Hohhot)>Ningxia hub(Yinchuan)>Yangtze River Delta hub(Shanghai)>Chengdu Chongqing hub(Chongqing)>Guangdong-Hong Kong-Macao Greater Bay Area hub(Guangzhou)>Guizhou hub(Guiyang)>Beijing-Tianjin-Hebei hub(Beijing).Furthermore,Hohhot,Lanzhou,and Yinchuan consistently rank among the top three cities for comprehensive scores across all load rates,while Guiyang(at a 25%load rate),Guangzhou(at a 50%load rate),and Beijing(at 75%and 100%load rates)exhibited the lowest comprehensive scores.展开更多
The analysis refers to the interwar years in Europe.We distinguish four types of coalitions here:(a)Coalitions with other democratic parties,led by a predominant party and most common in multi-party democratic states....The analysis refers to the interwar years in Europe.We distinguish four types of coalitions here:(a)Coalitions with other democratic parties,led by a predominant party and most common in multi-party democratic states.(b)Bringing in ideological opponents on the parts of overarching highly credible national figures such as King George V did in Britain in 1931 in calling upon the charismatic Labour Party leader MacDonald to form a coalition with the still dominant but ailing Conservative Party.(c)The outbidding of more radical political parties by former center parties towards the right or left.One such outcome comes about when this is having a temporary effect only,until the next election is won within the family of democratic parties.Yet,when outbidding is trump the electorate easily might go for the hardest outbidding contender not to be taken over by even greater extremist parties.This process for the analysis of political terrorism and its intention to instigate fear amongst the“neutral”population explains to a large extent why considerable portions of the population are going to side with the most extreme challengers.This is for two reasons,one is pure fear to be out-mastered,the other one is rational choice just to avoid this.(d)The other outcome as to outbidding occurs when the democratic national consensus formation that is still underlying all these processes in normal times is wiped out in times of crises.Democratic national consensus is being lost vis-à-vis a new anti-democratic national consensus formation.Several other theoretical arguments and historical experiences are touched upon.展开更多
Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrog...Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrogen-vacancy(NV)centers in diamond,have demonstrated remarkable capabilities in this domain[1–4].However,these systems are limited by their rigid lattice structures and lack tunability.展开更多
Qualitative methods of ordinary differential equation and Liapunov center theorem were used to study the existence of periodic solutions for higher order autonomous Birkhoff systems. For higher order autonomous Birkho...Qualitative methods of ordinary differential equation and Liapunov center theorem were used to study the existence of periodic solutions for higher order autonomous Birkhoff systems. For higher order autonomous Birkhoff systems, the character of the characteristic roots of the Fréchet derivative C was obtained. Furthermore the existence theorem of periodic solutions was obtained by using Liapunov center theorem, and an example was presented to illustrate the results.展开更多
To obtain accurate forms and surfaces in free surface grinding, it is important to provide grinding conditions suitable for a curved surface. A grinding support system for the free surface （GSX-F） is proposed to hel...To obtain accurate forms and surfaces in free surface grinding, it is important to provide grinding conditions suitable for a curved surface. A grinding support system for the free surface （GSX-F） is proposed to help the operator grind a free surface with the high accuracy and the high productivity. To succeed in free surface grinding, the property of a ball type wheel must be known. Therefore, a basic study of free surface grinding with a ball type wheel is carried out based on the grinding center （GC）. Some working points for achieving sufficient accuracy in free surface grinding are discussed. GSX-F is constructed using the patch division method and is used to test grinding. Reasonable results are obtained.展开更多
Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 i...Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 is designed in order to acquire gas pressure during cluster bombs dispersion.To meet the requirement of low power consumption,the working states of system＇s modules during data acquisition are elaborated and the equation to calculate the gas pressure change during cylindrical center tube opening the hatch is deduced.The field test is conducted and good test results are obtained.展开更多
High-entropy materials(HEMs),characterized by their unique compositional diversity and configurational entropy,have emerged as promising candidates in the field of photocatalysis.These materials,typically composed of ...High-entropy materials(HEMs),characterized by their unique compositional diversity and configurational entropy,have emerged as promising candidates in the field of photocatalysis.These materials,typically composed of five or more principal elements,exhibit remarkable structural stability,enhanced electronic properties,and superior resistance to corrosion and oxidation.In the realm of photocatalysis,HEMs offer several advantages,including broad spectral absorption,efficient charge separation,and robust catalytic activity under various environmental conditions.This review summarizes recent advancements in the synthesis,characterization,and application of HEMs for photocatalytic processes,such as H_(2)evolution,CO_(2)conversion,organic pollutant degradation,and organic conversion.By exploring the intrinsic properties of HEMs and their synergistic effects,we aim to highlight their potential to revolutionize the design and development of next-generation photocatalysts.The integration of HEMs into photocatalytic systems not only paves the way for more efficient and sustainable energy conversion technologies but also opens new avenues for environmental remediation.展开更多
Overcoming kinetic limitations in the acidic oxygen reduction reaction(ORR)demands Pt-based catalysts with optimized surface adsorption.Herein,we engineer hierarchical PtPd dendrite nanocrystals(PtPd NDs)featuring pre...Overcoming kinetic limitations in the acidic oxygen reduction reaction(ORR)demands Pt-based catalysts with optimized surface adsorption.Herein,we engineer hierarchical PtPd dendrite nanocrystals(PtPd NDs)featuring precisely tailored asymmetric sites and high-index facets(HIFs)to overcome the kinetic limitations in acidic media.Controlled Pd incorporation disrupts symmetry of the single-oriented crystal plane,generating inhomogeneous strain and promoting HIFs exposure.This synergistic structural engineering optimizes the adsorption/desorption of oxygen-containing intermediates,significantly accelerating ORR kinetics.Consequently,PtPd NDs deliver exceptional mass activity(MA=1.37 A mg_(Pt)^(-1),11.42 times higher than Pt/C)and remarkable stability(83.9%MA retention after durability testing).In H_(2)-Air fuel cells,PtPd NDs also achieve higher peak power density versus Pt/C cathodes.In situ synchrotron radiation infrared spectroscopy and theoretical studies reveal that the synergistic effect between asymmetric sites and HIFs stimulates the strain field and causes a downward shift in the d-band center,thereby lowering the*OOH formation barrier and weakening intermediate adsorption,directly boosting the ORR performance.This work underscores the critical role of facet and site engineering in designing high-performance fuel cell electrocatalysts.展开更多
The Mountain Science Data Center(MSDC),founded in 2021 under the Institute of Mountain Hazards and Environment(IMHE),Chinese Academy of Sciences,manages the entire lifecycle of mountain science data.It integrates data...The Mountain Science Data Center(MSDC),founded in 2021 under the Institute of Mountain Hazards and Environment(IMHE),Chinese Academy of Sciences,manages the entire lifecycle of mountain science data.It integrates data from diverse sources,including debris flows,landslides,soils,ecology,geology,natural resources,basic geographic information,and socio-economic data.The center provides comprehensive services,including data collection,processing,analysis tools,modeling,and application support,offering reliable data backing for numerous research projects within the institute.Data management and services are accessible via the Mountain Science Data Center Portal(https://www.msdc.ac.cn/),ensuring long-term,stable,and trustworthy access to facilitate scientific research and institutional development.展开更多
NCPA Drama Commission:Suspect Sherlock Holmes Date:February 5-14,2026 Venue:National Center for the Performing Arts As the first suspense drama commission to be produced by the NCPA,Suspect Holmes is derived from a le...NCPA Drama Commission:Suspect Sherlock Holmes Date:February 5-14,2026 Venue:National Center for the Performing Arts As the first suspense drama commission to be produced by the NCPA,Suspect Holmes is derived from a legendary detective story,featuring iconic characters including Sherlock Holmes,John Watson,Professor Moriarty,Mycroft Holmes,policeman Lestrade,and Mrs.Hudson.展开更多
Organic-inorganic metal halides(OIMHs)have emerged as highly promising novel multifunctional optoelectronic materials,owing to their easily adjustable properties from a variety of combinations of different components....Organic-inorganic metal halides(OIMHs)have emerged as highly promising novel multifunctional optoelectronic materials,owing to their easily adjustable properties from a variety of combinations of different components.But it is still difficult and rare to realize highly tunable multicolor luminescence within the same material.In this work,we successfully incorporated three adjustable emission centers in OIMHs to synthesize a novel OIMH(NEA)_(2)MnBr_(4),with each emission center capable of emitting one of the primary colors—red,green,and blue.The green and red emissions originate from the tetrahedron and octahedron structures in the Mn-based frame,while the blue can be attributed to the contribution of organic components.Additionally,to achieve comparable emission intensity among the three primary colors,we enhanced the blue emission performance by optimizing the ratio of organic structure components and incorporating chirality in the OIMHs.The resulting high-quality films can be obtained by spin-coating method with a photoluminescence quantum yields of up to 96%.More interestingly,by the dual manipulation of excitation wavelength and temperature,the sample can be emitted at least seven distinct colors including a standard white luminescence at(0.33,0.33),opening up promising prospects for multicolor luminescence applications such as high-end anti-counterfeiting technology,light-emitting diodes,X-ray imaging,latent fingerprints,humidity detection,and so on.Therefore,based on application scenarios and requirements,our research on this highly tunable luminescent OIMH material lays a solid foundation for further development of various functional properties of related materials.展开更多
Siemens and Yangpu Economic Development Zone in Hainan have forged a close partnership in a journey towards green energy transition.SIEMENS Energy,one of the world’s leading energy technology companies,became the fir...Siemens and Yangpu Economic Development Zone in Hainan have forged a close partnership in a journey towards green energy transition.SIEMENS Energy,one of the world’s leading energy technology companies,became the first foreign-funded manufacturer to establish a branch and began construction of a gas turbine assembly base and service center in Hainan on December 18,2025.展开更多
The 20th Communist Party of China(CPC)Central Committee held its fourth plenary session in Beijing on October 20-23.The plenary session's central task was to deliberate on the framework of the country's next n...The 20th Communist Party of China(CPC)Central Committee held its fourth plenary session in Beijing on October 20-23.The plenary session's central task was to deliberate on the framework of the country's next national development roadmap:the 15th Five-Year Plan(2026-2030).Every five-year plan is important but this one arrives at a truly pivotal moment in terms of China's development trajectory and the global environment.展开更多
The problem of time delay speed feedback in the control loop is considered here.Its effects on the linear stability and dynamic behavior of the maglev system are investigated.It is found that a Hopf bifurcation can ta...The problem of time delay speed feedback in the control loop is considered here.Its effects on the linear stability and dynamic behavior of the maglev system are investigated.It is found that a Hopf bifurcation can take place when the time delay exceeds certain values.The stability condition of the maglev system with the time delay is acquired.The direction and stability of the Hopf bifurcation are determined by constructing a center manifold and by applying the normal form method.Finally,numerical simulations are performed to verify the analytical result.展开更多
To implement five-axis functions in CNC system, based on domestic system Lan Tian series, an improved design method for the system software structure is proposed in this paper. The numerical control kernel of CNC syst...To implement five-axis functions in CNC system, based on domestic system Lan Tian series, an improved design method for the system software structure is proposed in this paper. The numerical control kernel of CNC system is divided into the task layer and the motion layer. A five-axis transformation unit is integrated into the motion layer. After classifying five-axis machines into different types and analyzing their geometry information, the five-axis kinematic library is designed according to the abstract factory pattern. Furthermore, by taking CA spindle- tilting machine as an example, the forward and the inverse kinematic transformations are deduced. Based on the new software architecture and the five-axis kinematic library, algorithms of RTCP （rotation tool center point control） and 3D radius compensation for end-milling are designed and realized. The milling results show that, with five-axis functions based on such software struc- ture, the instructions with respect to the cutter＇s position and orientation can be directly carried out in the CNC system.展开更多
基金Graduate Innovation Ability Training Program of the Hebei Provincial Department of Education,2025(Project No.:CXZZSS2025095)。
文摘This paper designs and implements a single-camera 360°panoramic imaging system based on motor-driven fisheye rotation.The system utilizes a stepper motor for precise angular control,enabling the camera to rotate around its optical center to capture multi-view images,thereby avoiding the parallax and geometric mismatch problems inherent in traditional multi-camera configurations.To address the strong distortion characteristics of fisheye images,an equidistant projection model is adopted for distortion correction.On this basis,a brightness normalization method combining global linear brightness correction and local illumination compensation is proposed to enhance stitching consistency.By establishing a geometry model constrained by camera rotation and integrating cylindrical projection with cosine-weighted blending,the system achieves high-precision panoramic stitching and seamless visual transitions.
基金supported in part by the National Natural Science Foundation of China under Grant 52177082in part by the Beijing Nova Program under Grant 20220484007.
文摘With the advent of the digital economy,there has been a rapid proliferation of small-scale Internet data centers(SIDCs).By leveraging their spatiotemporal load regulation potential through data workload balancing,aggregated SIDCs have emerged as promising demand response(DR)resources for future power distribution systems.This paper presents an innovative framework for assessing capacity value(CV)by aggregating SIDCs participating in DR programs(SIDC-DR).Initially,we delineate the concept of CV tailored for aggregated SIDC scenarios and establish a metric for the assessment.Considering the effects of the data load dynamics,equipment constraints,and user behavior,we developed a sophisticated DR model for aggregated SIDCs using a data network aggregation method.Unlike existing studies,the proposed model captures the uncertainties associated with end tenant decisions to opt into an SIDC-DR program by utilizing a novel uncertainty modeling approach called Z-number formulation.This approach accounts for both the uncertainty in user participation intentions and the reliability of basic information during the DR process,enabling high-resolution profiling of the SIDC-DR potential in the CV evaluation.Simulation results from numerical studies conducted on a modified IEEE-33 node distribution system confirmed the effectiveness of the proposed approach and highlighted the potential benefits of SIDC-DR utilization in the efficient operation of future power systems.
文摘As the cornerstone of sterile instrument maintenance in endoscopy centers,the quality of endoscope cleaning directly impacts hospital infection control effectiveness.The traceability system for endoscopy centers utilizes digital means to document the entire cleaning process,enabling real-time monitoring and precise quality control.This paper analyzes current quality control practices in endoscope cleaning and addresses existing challenges.It explores how traceability systems standardize procedures,enhance monitoring,and improve management efficiency.The study proposes optimization strategies for traceability system implementation,clarifying its core value in endoscope cleaning quality control.These findings provide theoretical foundations and practical guidance for hospitals to refine management of endoscopy centers,ensure diagnostic safety,and reduce infection risks,ultimately advancing endoscope cleaning quality control toward standardized and informatized development.
基金supported by the Natural Science Foundation of Hunan Province,China(Grant Nos.2023JJ50178 and 2023JJ50194)the Excellent Youth Project of Hunan Provincial Department of Education(Grant No.23B0542).
文摘Rack-level loop thermosyphons have been widely adopted as a solution to data centers’growing energy demands.While numerous studies have highlighted the heat transfer performance and energy-saving benefits of this system,its economic feasibility,water usage effectiveness(WUE),and carbon usage effectiveness(CUE)remain underexplored.This study introduces a comprehensive evaluation index designed to assess the applicability of the rack-level loop thermosyphon system across various computing hub nodes.The air wet bulb temperature Ta,w was identified as the most significant factor influencing the variability in the combination of PUE,CUE,and WUE values.The results indicate that the rack-level loop thermosyphon system achieves the highest score in Lanzhou(94.485)and the lowest in Beijing(89.261)based on the comprehensive evaluation index.The overall ranking of cities according to the comprehensive evaluation score is as follows:Gansu hub(Lanzhou)>Inner Mongolia hub(Hohhot)>Ningxia hub(Yinchuan)>Yangtze River Delta hub(Shanghai)>Chengdu Chongqing hub(Chongqing)>Guangdong-Hong Kong-Macao Greater Bay Area hub(Guangzhou)>Guizhou hub(Guiyang)>Beijing-Tianjin-Hebei hub(Beijing).Furthermore,Hohhot,Lanzhou,and Yinchuan consistently rank among the top three cities for comprehensive scores across all load rates,while Guiyang(at a 25%load rate),Guangzhou(at a 50%load rate),and Beijing(at 75%and 100%load rates)exhibited the lowest comprehensive scores.
文摘The analysis refers to the interwar years in Europe.We distinguish four types of coalitions here:(a)Coalitions with other democratic parties,led by a predominant party and most common in multi-party democratic states.(b)Bringing in ideological opponents on the parts of overarching highly credible national figures such as King George V did in Britain in 1931 in calling upon the charismatic Labour Party leader MacDonald to form a coalition with the still dominant but ailing Conservative Party.(c)The outbidding of more radical political parties by former center parties towards the right or left.One such outcome comes about when this is having a temporary effect only,until the next election is won within the family of democratic parties.Yet,when outbidding is trump the electorate easily might go for the hardest outbidding contender not to be taken over by even greater extremist parties.This process for the analysis of political terrorism and its intention to instigate fear amongst the“neutral”population explains to a large extent why considerable portions of the population are going to side with the most extreme challengers.This is for two reasons,one is pure fear to be out-mastered,the other one is rational choice just to avoid this.(d)The other outcome as to outbidding occurs when the democratic national consensus formation that is still underlying all these processes in normal times is wiped out in times of crises.Democratic national consensus is being lost vis-à-vis a new anti-democratic national consensus formation.Several other theoretical arguments and historical experiences are touched upon.
文摘Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrogen-vacancy(NV)centers in diamond,have demonstrated remarkable capabilities in this domain[1–4].However,these systems are limited by their rigid lattice structures and lack tunability.
文摘Qualitative methods of ordinary differential equation and Liapunov center theorem were used to study the existence of periodic solutions for higher order autonomous Birkhoff systems. For higher order autonomous Birkhoff systems, the character of the characteristic roots of the Fréchet derivative C was obtained. Furthermore the existence theorem of periodic solutions was obtained by using Liapunov center theorem, and an example was presented to illustrate the results.
文摘To obtain accurate forms and surfaces in free surface grinding, it is important to provide grinding conditions suitable for a curved surface. A grinding support system for the free surface （GSX-F） is proposed to help the operator grind a free surface with the high accuracy and the high productivity. To succeed in free surface grinding, the property of a ball type wheel must be known. Therefore, a basic study of free surface grinding with a ball type wheel is carried out based on the grinding center （GC）. Some working points for achieving sufficient accuracy in free surface grinding are discussed. GSX-F is constructed using the patch division method and is used to test grinding. Reasonable results are obtained.
文摘Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 is designed in order to acquire gas pressure during cluster bombs dispersion.To meet the requirement of low power consumption,the working states of system＇s modules during data acquisition are elaborated and the equation to calculate the gas pressure change during cylindrical center tube opening the hatch is deduced.The field test is conducted and good test results are obtained.
基金financially supported by the Eastern Institute of Technology,Ningbo。
文摘High-entropy materials(HEMs),characterized by their unique compositional diversity and configurational entropy,have emerged as promising candidates in the field of photocatalysis.These materials,typically composed of five or more principal elements,exhibit remarkable structural stability,enhanced electronic properties,and superior resistance to corrosion and oxidation.In the realm of photocatalysis,HEMs offer several advantages,including broad spectral absorption,efficient charge separation,and robust catalytic activity under various environmental conditions.This review summarizes recent advancements in the synthesis,characterization,and application of HEMs for photocatalytic processes,such as H_(2)evolution,CO_(2)conversion,organic pollutant degradation,and organic conversion.By exploring the intrinsic properties of HEMs and their synergistic effects,we aim to highlight their potential to revolutionize the design and development of next-generation photocatalysts.The integration of HEMs into photocatalytic systems not only paves the way for more efficient and sustainable energy conversion technologies but also opens new avenues for environmental remediation.
基金supported by Yunnan Province Key Research and Development Program(202503AA080007)the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd.(YPML-20240502051and YPML-2023050204)+1 种基金the National Natural Science Foundation of China(12405377)the Science and Technology Planning Project of Yunnan Province(202302AH360001)。
文摘Overcoming kinetic limitations in the acidic oxygen reduction reaction(ORR)demands Pt-based catalysts with optimized surface adsorption.Herein,we engineer hierarchical PtPd dendrite nanocrystals(PtPd NDs)featuring precisely tailored asymmetric sites and high-index facets(HIFs)to overcome the kinetic limitations in acidic media.Controlled Pd incorporation disrupts symmetry of the single-oriented crystal plane,generating inhomogeneous strain and promoting HIFs exposure.This synergistic structural engineering optimizes the adsorption/desorption of oxygen-containing intermediates,significantly accelerating ORR kinetics.Consequently,PtPd NDs deliver exceptional mass activity(MA=1.37 A mg_(Pt)^(-1),11.42 times higher than Pt/C)and remarkable stability(83.9%MA retention after durability testing).In H_(2)-Air fuel cells,PtPd NDs also achieve higher peak power density versus Pt/C cathodes.In situ synchrotron radiation infrared spectroscopy and theoretical studies reveal that the synergistic effect between asymmetric sites and HIFs stimulates the strain field and causes a downward shift in the d-band center,thereby lowering the*OOH formation barrier and weakening intermediate adsorption,directly boosting the ORR performance.This work underscores the critical role of facet and site engineering in designing high-performance fuel cell electrocatalysts.
文摘The Mountain Science Data Center(MSDC),founded in 2021 under the Institute of Mountain Hazards and Environment(IMHE),Chinese Academy of Sciences,manages the entire lifecycle of mountain science data.It integrates data from diverse sources,including debris flows,landslides,soils,ecology,geology,natural resources,basic geographic information,and socio-economic data.The center provides comprehensive services,including data collection,processing,analysis tools,modeling,and application support,offering reliable data backing for numerous research projects within the institute.Data management and services are accessible via the Mountain Science Data Center Portal(https://www.msdc.ac.cn/),ensuring long-term,stable,and trustworthy access to facilitate scientific research and institutional development.
文摘NCPA Drama Commission:Suspect Sherlock Holmes Date:February 5-14,2026 Venue:National Center for the Performing Arts As the first suspense drama commission to be produced by the NCPA,Suspect Holmes is derived from a legendary detective story,featuring iconic characters including Sherlock Holmes,John Watson,Professor Moriarty,Mycroft Holmes,policeman Lestrade,and Mrs.Hudson.
基金supported by supported by the Basic Research Project of State Key Laboratory of Photovoltaic Science and Technology(No.202401020302)funding support from the National Natural Science Foundation of China(No.62274040 and No.62304046)Shanghai science and technology innovation action plan(No.24DZ3001200)。
文摘Organic-inorganic metal halides(OIMHs)have emerged as highly promising novel multifunctional optoelectronic materials,owing to their easily adjustable properties from a variety of combinations of different components.But it is still difficult and rare to realize highly tunable multicolor luminescence within the same material.In this work,we successfully incorporated three adjustable emission centers in OIMHs to synthesize a novel OIMH(NEA)_(2)MnBr_(4),with each emission center capable of emitting one of the primary colors—red,green,and blue.The green and red emissions originate from the tetrahedron and octahedron structures in the Mn-based frame,while the blue can be attributed to the contribution of organic components.Additionally,to achieve comparable emission intensity among the three primary colors,we enhanced the blue emission performance by optimizing the ratio of organic structure components and incorporating chirality in the OIMHs.The resulting high-quality films can be obtained by spin-coating method with a photoluminescence quantum yields of up to 96%.More interestingly,by the dual manipulation of excitation wavelength and temperature,the sample can be emitted at least seven distinct colors including a standard white luminescence at(0.33,0.33),opening up promising prospects for multicolor luminescence applications such as high-end anti-counterfeiting technology,light-emitting diodes,X-ray imaging,latent fingerprints,humidity detection,and so on.Therefore,based on application scenarios and requirements,our research on this highly tunable luminescent OIMH material lays a solid foundation for further development of various functional properties of related materials.
文摘Siemens and Yangpu Economic Development Zone in Hainan have forged a close partnership in a journey towards green energy transition.SIEMENS Energy,one of the world’s leading energy technology companies,became the first foreign-funded manufacturer to establish a branch and began construction of a gas turbine assembly base and service center in Hainan on December 18,2025.
文摘The 20th Communist Party of China(CPC)Central Committee held its fourth plenary session in Beijing on October 20-23.The plenary session's central task was to deliberate on the framework of the country's next national development roadmap:the 15th Five-Year Plan(2026-2030).Every five-year plan is important but this one arrives at a truly pivotal moment in terms of China's development trajectory and the global environment.
基金Supported by National Natural Science Foundation of China(604040037 and Fork Ying-Dong Education Foundation(94028)
文摘The problem of time delay speed feedback in the control loop is considered here.Its effects on the linear stability and dynamic behavior of the maglev system are investigated.It is found that a Hopf bifurcation can take place when the time delay exceeds certain values.The stability condition of the maglev system with the time delay is acquired.The direction and stability of the Hopf bifurcation are determined by constructing a center manifold and by applying the normal form method.Finally,numerical simulations are performed to verify the analytical result.
基金supported by the National Basic Research Program of China (No. 2011CB302400)the Important National Science & Technology Specific Projects (No. 2013ZX04007031).
文摘To implement five-axis functions in CNC system, based on domestic system Lan Tian series, an improved design method for the system software structure is proposed in this paper. The numerical control kernel of CNC system is divided into the task layer and the motion layer. A five-axis transformation unit is integrated into the motion layer. After classifying five-axis machines into different types and analyzing their geometry information, the five-axis kinematic library is designed according to the abstract factory pattern. Furthermore, by taking CA spindle- tilting machine as an example, the forward and the inverse kinematic transformations are deduced. Based on the new software architecture and the five-axis kinematic library, algorithms of RTCP （rotation tool center point control） and 3D radius compensation for end-milling are designed and realized. The milling results show that, with five-axis functions based on such software struc- ture, the instructions with respect to the cutter＇s position and orientation can be directly carried out in the CNC system.
