In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)r...In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)receive widespread attention in practical energy storage applications due to their unique oriented thermally conductive structure,which achieves significant thermal conductivity enhancement in specific directions while retaining the high energy storage capacity of the phase change components.This review systematically summarizes the overall analysis of OCPCMs from synthesis and preparation to application scenarios in recent years.Herein,we introduce the analysis of the heat transfer mechanism of the materials and explore the advantages of the oriented structure in OCPCMs in the heat transfer behavior from a bionic perspective.We then focus on summarizing and generalizing the methods for preparing OCPCMs,giving suggestions for suitable methods according to different scenarios.Besides,we discuss the application of finite element simulation methods to the monitoring of the thermal management behavior of OCPCMs,and look into the potential future application areas of such materials.Finally,it is hoped that this review will provide guidance for the academic community in developing high-performance OCPCMs.展开更多
Systematically analyzing the impact mechanisms of policy on Land Use Conflict(LUC)is crucial for constructing effective conflict mitigation strategies.However,previous research on how policy influences LUC remains rel...Systematically analyzing the impact mechanisms of policy on Land Use Conflict(LUC)is crucial for constructing effective conflict mitigation strategies.However,previous research on how policy influences LUC remains relatively limited.Focusing on the indirect driving role of policy on LUC,this study proposed County Development Level(CDL)under Major Function Oriented Zone Planning(MFOZP)guidance as an intermediary variable,bridging the implicit influence of MFOZP and the explicit changes in LUC.Using the Beijing-Tianjin-Hebei(BTH)region in China as a case study,we analyzed the spatio-temporal evolution characteristics of LUC and CDL for the periods 2000-2010 and 2010-2020,before and after MFOZP implementation.Panel models and Geographically Weighted Regression(GWR)were employed to explore the mechanism by which CDL influences LUC under MFOZP guidance.The results show that:1)MFOZP implementation effectively alleviates land use pressure from regional development,with LUC continuously declining at a rate of 2.41%,while CDL exhibits slight growth(3.84%),during 2010-2020.2)Under MFOZP guidance,CDL reduces pressure on Land Use Structure Conflict(LUSC)and Land Use Process Conflict(LUPC),enhances its inhibitory effect on Land Use Function Conflict(LUFC),and significantly contributes to LUC coordination,with notable spatial heterogeneity.3)The coupling relationship between CDL and LUC has improved post-implementation.Based on this,tailored LUC coordination strategies are proposed for different functional zones.This study confirms the effectiveness of MFOZP in coordinating LUC and provides a scientific reference for LUC research under policy frameworks and the governance of LUC in the BTH region.展开更多
High energy synchrotron diffraction offers great potential to study the recrystallization kinetics of metallic materials. To study the formation of Goss texture （{ [10}（001）） of grain oriented （GO） silicon steel...High energy synchrotron diffraction offers great potential to study the recrystallization kinetics of metallic materials. To study the formation of Goss texture （{ [10}（001）） of grain oriented （GO） silicon steel during secondary recrystallization process, an in situ experiment using hi gh energy X-ray diffraction was designed. The results showed that the secondary recrystallization began when the heating temperature was 1,494 K, and the grains grew rapidly above this temperature. With an increase in annealing temperature, the large grains with 7 orientation [〈111〉//normal direction] formed and gradually occupied the dominant position. As the annealing temperature increased even further, the grains with Goss orientation to a very large size by devouring the 7 orientation grains that formed in the early annealing stage. A single crystal with a Goss orientation was observed in the GO silicon steel when the annealing temperature was 1,540 K.展开更多
In order to conduct effective reliability analysis of retracting actuator with multi-state(success state,safety failure state and action failure state), we redefine type-3 operator in goal oriented(GO) method to descr...In order to conduct effective reliability analysis of retracting actuator with multi-state(success state,safety failure state and action failure state), we redefine type-3 operator in goal oriented(GO) method to describe three states of main charge of retracting actuator and improve type-15 operator in GO method to describe the logic relations of multi-state output. The quantitative and qualitative reliability analyses of retracting actuator are made based on GO method in this paper. The system state probability of retracting actuator is obtained through quantitative analysis, and its weakness is found through qualitative analysis. The analysis results show that GO method is effective to improve the reliability of retracting actuator, and this method is also feasible for reliability analysis of other complicated initiating explosive systems.展开更多
Goal oriented( GO) methodology is a kind of success oriented system reliability analysis method and has been used widely.The repairable system with dual input closed-loop feedback link( DICLFL) considering shutdown co...Goal oriented( GO) methodology is a kind of success oriented system reliability analysis method and has been used widely.The repairable system with dual input closed-loop feedback link( DICLFL) considering shutdown correlation didn't make reliability analysis accurately based on existing GO methodology. So, a reliability analysis method used to deal with DICLFL considering shutdown correlation is provided based on GO methodology.Firstly, a new operator, which is used to describe DICLFL considering shutdown correlation,whose number is 1,is created and named as Type 9C operator. And then,the formulas of type 9C operator are derived based on Markov process theory. Finally,the new method presented in this paper is adopted to conduct the reliability analysis of an electro-hydraulic servo speed control system. The analysis result is compared with those of Monte Carlo simulation and fault tree analysis( FTA). The comparison results show that this new reliability analysis method based on GO methodology is feasible and meaningful for reliability analysis of repairable systems with DICLFL considering shutdown correlation.Meantime,it will be useful for more other applications.展开更多
As an efficient artificial truncating boundary condition, conformal perfectly matched layer (CPML) is a kind of multilayer anisotropic absorbing media. To reduce computing effort of CPML, this article proposes a layer...As an efficient artificial truncating boundary condition, conformal perfectly matched layer (CPML) is a kind of multilayer anisotropic absorbing media. To reduce computing effort of CPML, this article proposes a layer-oriented element integration algorithm. In this algorithm, the relative dielectric constant and permeability are considered as constants for each the very thin monolayer of CPML, and the element integration of multilayer along the normal direction is substituted by the element integration of m...展开更多
A simple electrochemical method for the in situ preparation of homogeneously dispersed gold-polyaniline core/shell nanocomposite particles with controlled size on the highly oriented pyrolytic graphite(HOPG)was demons...A simple electrochemical method for the in situ preparation of homogeneously dispersed gold-polyaniline core/shell nanocomposite particles with controlled size on the highly oriented pyrolytic graphite(HOPG)was demonstrated.The HOPG surface was modified preferentially by covalent bonding of a two-dimensional 4-aminophenyl monolayer employing diazonium chemistry.AuCl4 -ions were attached to the Ar-NH2 termination and reduced electrochemically.This results in the formation of Au nuclei that could be further grown into gold nanoparticles.The formation of polyaniline as the shell wrap of Au nanoparticle was established by localized electro-polymerization.These core-shell nanocomposites prepared were characterized by AFM and cyclic voltammetry.The results show that the gold-polyaniline core-shell composites on HOPG have a mean particle size of 100 nm in diameter and the polyaniline shell thickness is about 15 nm.展开更多
Preferential orientation control of metal—organic framework(MOF)films is advantageous for maximizing pore uniformity and minimizing grain-boundary defects.Nonetheless,the preparation of MOF films with both in-plane a...Preferential orientation control of metal—organic framework(MOF)films is advantageous for maximizing pore uniformity and minimizing grain-boundary defects.Nonetheless,the preparation of MOF films with both in-plane and out-of-plane orientations remains a grand challenge.In this study,we reported the preparation of three-dimensionally oriented MIL-96 layers through combining morphology control of MIL-96 seeds with addition of polyvinylpyrrolidone surfactants and arachidonic acids.The three-dimensionally oriented MIL-96 film was readily obtained through in-plane epitaxial growth.It is anticipated that the aforementioned protocol can be effective for obtaining diverse MOF films with a three-dimensionally oriented organization.展开更多
Based on the state governance background of peasant household oriented land circulation,I analyzed characteristics of peasant household oriented land circulation.The characteristics mainly include uncertain definition...Based on the state governance background of peasant household oriented land circulation,I analyzed characteristics of peasant household oriented land circulation.The characteristics mainly include uncertain definition of rural land circulation,significant off-media feature of land circulation,long-term land circulation contract,farmers' preference of peasant household oriented land circulation,and progressive path of land circulation.The essential feature is the progressive mode of land circulation.Under the existing property right,it realizes the perfect combination of modern production factors and traditional agricultural,and the combination of traditional family safeguarding function and modern social mutual growth spirit.Thus,it shows relative independence and manifests the idea of common prosperity.The opportunity cost of peasant household oriented land circulation is minimal,institutional cost will increase circulation risk,and what's more,the cost for state governance of peasant household oriented land circulation is minimal.It comes to conclusion that building proper and harmonious land circulation mechanism is responsibility of central government and favorable for healthy development of peasant household oriented land circulation.展开更多
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the...Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.展开更多
In this study, high- and low-grade grain-oriented electrical steels were used as the initial materials to produce 0.08-mm-thick sheet with one-step cold-rolling method. Electron backscattering diffraction analysis tec...In this study, high- and low-grade grain-oriented electrical steels were used as the initial materials to produce 0.08-mm-thick sheet with one-step cold-rolling method. Electron backscattering diffraction analysis technique and X-ray diffraction texture analysis technique were adopted to investigate the effect of initial Goss texture sharpness on texture evolution and magnetic properties of ultra-thin grain-oriented electrical steel. The results showed that primary recrystal- lization and secondary recrystallization were the main processes that occurred during annealing. The induced factors for secondary recrystallization of two grades samples were not Consistent. The high-grade samples presented texture induction mechanism, while the low-grade samples revealed strong surface-energy induction mechanism. The initial Goss texture sharpness had a great impact on texture evolution and magnetic properties of ultra-thin grain-oriented electrical steel. The Goss texture component formed after primary recrystallization was stronger, and better magnetic properties were obtained at low frequencies. For low-grade samples, secondary recrystallization enhanced the intensity of Goss texture, and both grain size and texture contributed to better high-frequency magnetic properties after secondary recrystallization. By controlling the annealing process, the magnetic properties of low-grade products could be significantly improved, thus achieving conversion from low-grade to high-grade products.展开更多
With the help of electron back scattering diffraction techniques and field emission microscope, the misorienta- tion and the precipitation environment of Goss grains in conventional grain-oriented steel were observed ...With the help of electron back scattering diffraction techniques and field emission microscope, the misorienta- tion and the precipitation environment of Goss grains in conventional grain-oriented steel were observed and investigated at the initial stage of secondary recrystallization. It reveals that the abnormal Goss grains have a high fraction of high angle boundaries ranging from 25 to 40 deg. The most important observation is that some of {110}〈001〉 grains in matrix indicated higher particle density than their neighbor grains during final annealing at 875℃ before secondary recrystallization, which could create a favorable environment for their abnormal grain growth. Based on misorientation and precipitation results, the abnormal growth mechanism of Goss grains was sketched.展开更多
Inhibiting dendrites formation and side-reactions is a critical challenge for practical application of aqueous Zn-ion batteries(AZIBs).Electrolyte additives offer an effective solution to address this problem.Inspired...Inhibiting dendrites formation and side-reactions is a critical challenge for practical application of aqueous Zn-ion batteries(AZIBs).Electrolyte additives offer an effective solution to address this problem.Inspired by using green corrosion inhibitor for metals,we introduce caffeine,extracted from tea-leaf,as an additive to achieve stable AZIBs.Caffeine,with its N and O containing groups,strongly adsorbs on the Zn anode and Zn^(2+)ions.This featured adsorption induces the replacement of water molecules from electric double layer(EDL)and solvation shell,suppressing side-reactions such as corrosion and hydrogen evolution reaction(HER).Moreover,the selective adsorption and steric hindrance of caffeine promote Zn(002)-oriented deposition,resulting in uniform and compact zinc deposits at both low and high current density and areal capacity.Due to the significantly suppressed dendrites and corrosion,the Coulomb Efficiency(CE)reaches 99.24%after 800 cycles,and the Zn||MnO_(2)battery shows a specific capacity of 167.2 mAh g^(−1)with 81%capacity retention after 1000 cycles at 2 A g^(−1).展开更多
After graduating from the China Academy of Arts(Department of Oil Painting)in Hangzhou in 1995,Yang Fudong(1971)moved to Shanghai to work as a graphic designer.Inspired by his daily job in Pudong,he started producing ...After graduating from the China Academy of Arts(Department of Oil Painting)in Hangzhou in 1995,Yang Fudong(1971)moved to Shanghai to work as a graphic designer.Inspired by his daily job in Pudong,he started producing photographic series that closely resembled the advertising campaigns he worked on.Glossy images of stylish young people or dishevelled white collars in highly saturated colours,defined“intellectuals”in cryptic accompanying captions.Conversely,his body of work in black and white,almost entirely shot on 35mm film,portrays a suspended reality out of the historical time:a ghostly dimension akin to a drowsy vigil,a uchronia,an“estranged paradise”-to borrow the title of his earliest film set in Hangzhou.But it is Shanghai’s elusiveness and material relationship with the past that has contributed the most to form Yang’s trademark imagery and aesthetic.What he conjures up in his still and moving images,is a dimension with a distinctive oneiric quality,an“in-between”universe where all the circumstances are justified and have an inner logic,just like in dreams,or just like in the China of his childhood.The research of Yang Fudong is somewhat unique in the universe of contemporary Chinese art and sets him apart from a plethora of artists that have used the video in a much more“didactic”and quotational way.I will illustrate some specific aspects of his black and white body of work,trying to show how a certain self-orientalist trait can be interpreted as strategy to regain narrative agency and bring to the surface a series of removed instances:the main of which being,in my opinion,the fate of Shanghai’s(perhaps of China's Mainland in its ungraspable entirety?)modernity.展开更多
Chinese consumers browsing e-commerce platforms or walking in supermarket aisles have noticed a new feature:dedicated sections for high-quality export products.Far from being a mere marketing gimmick,this trend emerge...Chinese consumers browsing e-commerce platforms or walking in supermarket aisles have noticed a new feature:dedicated sections for high-quality export products.Far from being a mere marketing gimmick,this trend emerged due to intense pressure from a slide in global demand.展开更多
Cement occupies a significant proportion in construction,serving as the primary material for components such as bricks and walls.However,its role is largely limited to load-bearing functions,with little exploration of...Cement occupies a significant proportion in construction,serving as the primary material for components such as bricks and walls.However,its role is largely limited to load-bearing functions,with little exploration of additional applications.Simultaneously,buildings remain a major contributor to global energy consumption,accounting for 40%of total energy use.Here,we for the first time endow cement with energy storage functionality by developing cement-based solid-state energy storage wallboards(CSESWs),which can utilize the ample idle surface areas of building walls to seamlessly store renewable energy from distributed photovoltaics without compromising building safety or requiring additional space.Owing to unprecedented microstructures and composition interactions,these CSESWs not only achieve a superionic conductivity of 101.1 mS cm^(−1)but also demonstrate multifunctionality,such as significant toughness,thermal insulation,lightweight,and adhesion.When integrated with asymmetrical electrodes,the CSESWs exhibit a remarkable capacitance(2778.9 mF cm^(−2))and high areal energy density(10.8 mWhcm^(−2)).Moreover,existing residential buildings renovated with our CSESWs can supply 98%of daily electricity needs,demonstrating their outstanding potential for realizing zero-carbon buildings.This study pioneers the use of cement in energy storage,providing a scalable and cost-effective pathway for sustainable construction.展开更多
Flexible transparent antennas(FTAs)are widely used in wireless transmission fields,and their technological iterations are accelerating.However,the high losses caused by materials and structures limit the development o...Flexible transparent antennas(FTAs)are widely used in wireless transmission fields,and their technological iterations are accelerating.However,the high losses caused by materials and structures limit the development of FTAs with both high light transmission and high gain,and the rapid iteration rate demands greater process flexibility,which makes it difficult for existing technologies to achieve both demands.Here,we design a novel shell-core structure composite metal mesh(CMM)FTA to achieve extremely low skin depth loss and ohmic loss using skin effect and report a novel hybrid additive manufacturing method based on electric field oriented deposition to achieve efficient and flexible manufacturing of the unique Ag/Cu core-shell structure CMM FTA.The typical sample has a light transmittance of 80%(including substrate)when the sheet resistance is 0.29Ω·sq^(-1),and has excellent bending and torsion resistance.The peak gain in the working band is as high as 5.22 dB,and the efficiency is 80%,which is close to the performance of the opaque Cu patch antenna.It also realizes smooth and stable real-time wireless transmission under bending and long-distance conditions.This method addresses the shortcomings of FTAs,namely their high cost,low manufacturing efficiency,and low performance,especially in the rapid iterative development of antennas.展开更多
Rail positioning is a critical step for detecting rail defects downstream.However,existing orientation-based detectors struggle to effectively manage rails with arbitrary inclinations and high aspect ratios,particular...Rail positioning is a critical step for detecting rail defects downstream.However,existing orientation-based detectors struggle to effectively manage rails with arbitrary inclinations and high aspect ratios,particularly in turnout sections.To address these challenges,a fuzzy boundary guidance and oriented Gaussian function-based anchor-free network termed the rail positioning network(RP-Net)is proposed for rail positioning in turnout sections.First,an oriented Gaussian function-based label generation strategy is introduced.This strategy produces smoother and more accu-rate label values by accounting for the specific aspect ratios and orientations of the rails.Second,a fuzzy boundary learning module is developed to enhance the network’s abil-ity to model the rail boundary regions effectively.Further-more,a boundary guidance module is developed to direct the network in fusing the features obtained from the downs-ampled network output with the boundary region features,which have been enhanced to contain more refined posi-tional and structural information.A local channel attention mechanism is integrated into this module to identify critical channels.Finally,experiments conducted on the tracking dataset show that the proposed RP-Net achieves high posi-tioning accuracy and demonstrates strong adaptability in complex scenarios.展开更多
The evolution of energy storage technology has seen remarkable progress,with a shift from pure metals to sophisticated,tailor-made active materials.The synthesis of nanostructures with exceptional properties is crucia...The evolution of energy storage technology has seen remarkable progress,with a shift from pure metals to sophisticated,tailor-made active materials.The synthesis of nanostructures with exceptional properties is crucial in the advancement of electrode materials.In this regard,our study highlights the fabrication of a novel,oriented heterostructure comprised of Zn-Mn-Co-telluride grown on a pre-oxidized copper mesh using a hydrothermal method followed by a solvothermal process.This innovative approach leads to the formation of the Zn-Mn-Cotelluride@CuO@Cu heterostructure,which demonstrates the unique oriented morphology.It outperforms both Zn-Mn-Co-telluride@Cu and CuO@Cu by exhibiting lower electrical resistivity,increased redox activity,higher specific capacity,and improved ion diffusion characteristics.The conductivity enhancements of the heterostructure are corroborated by density functional theory(DFT)calculations.When utilized in a hybrid supercapacitor(HSC)alongside activated carbon(AC)electrodes,the Zn-Mn-Co-telluride@CuO@Cu heterostructurebased HSC achieves an energy density of 75.7 Wh kg^(-1).Such findings underscore the potential of these novel electrode materials to significantly impact the design of next-generation supercapacitor devices.展开更多
基金financially supported by the Fundamental Research Funds for the Central Universities(No.FRF-KST-25-001)the Beijing Natural Science Foundation(No.L253029)。
文摘In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)receive widespread attention in practical energy storage applications due to their unique oriented thermally conductive structure,which achieves significant thermal conductivity enhancement in specific directions while retaining the high energy storage capacity of the phase change components.This review systematically summarizes the overall analysis of OCPCMs from synthesis and preparation to application scenarios in recent years.Herein,we introduce the analysis of the heat transfer mechanism of the materials and explore the advantages of the oriented structure in OCPCMs in the heat transfer behavior from a bionic perspective.We then focus on summarizing and generalizing the methods for preparing OCPCMs,giving suggestions for suitable methods according to different scenarios.Besides,we discuss the application of finite element simulation methods to the monitoring of the thermal management behavior of OCPCMs,and look into the potential future application areas of such materials.Finally,it is hoped that this review will provide guidance for the academic community in developing high-performance OCPCMs.
基金Under the auspices of the National Key Research and Development Program of China(No.2018YFD1100803)the Fundamental Research Fund for the Central Universities(Ph.D.Top Innovative Talents Fund of CUMTB)(No.BBJ2024029)。
文摘Systematically analyzing the impact mechanisms of policy on Land Use Conflict(LUC)is crucial for constructing effective conflict mitigation strategies.However,previous research on how policy influences LUC remains relatively limited.Focusing on the indirect driving role of policy on LUC,this study proposed County Development Level(CDL)under Major Function Oriented Zone Planning(MFOZP)guidance as an intermediary variable,bridging the implicit influence of MFOZP and the explicit changes in LUC.Using the Beijing-Tianjin-Hebei(BTH)region in China as a case study,we analyzed the spatio-temporal evolution characteristics of LUC and CDL for the periods 2000-2010 and 2010-2020,before and after MFOZP implementation.Panel models and Geographically Weighted Regression(GWR)were employed to explore the mechanism by which CDL influences LUC under MFOZP guidance.The results show that:1)MFOZP implementation effectively alleviates land use pressure from regional development,with LUC continuously declining at a rate of 2.41%,while CDL exhibits slight growth(3.84%),during 2010-2020.2)Under MFOZP guidance,CDL reduces pressure on Land Use Structure Conflict(LUSC)and Land Use Process Conflict(LUPC),enhances its inhibitory effect on Land Use Function Conflict(LUFC),and significantly contributes to LUC coordination,with notable spatial heterogeneity.3)The coupling relationship between CDL and LUC has improved post-implementation.Based on this,tailored LUC coordination strategies are proposed for different functional zones.This study confirms the effectiveness of MFOZP in coordinating LUC and provides a scientific reference for LUC research under policy frameworks and the governance of LUC in the BTH region.
基金supported by the Key Projects of the National Science & Technology Pillar Program (No. 2011BAE13B03)the Fundamental Research Funds for the Central Universities (No. N110502001)
文摘High energy synchrotron diffraction offers great potential to study the recrystallization kinetics of metallic materials. To study the formation of Goss texture （{ [10}（001）） of grain oriented （GO） silicon steel during secondary recrystallization process, an in situ experiment using hi gh energy X-ray diffraction was designed. The results showed that the secondary recrystallization began when the heating temperature was 1,494 K, and the grains grew rapidly above this temperature. With an increase in annealing temperature, the large grains with 7 orientation [〈111〉//normal direction] formed and gradually occupied the dominant position. As the annealing temperature increased even further, the grains with Goss orientation to a very large size by devouring the 7 orientation grains that formed in the early annealing stage. A single crystal with a Goss orientation was observed in the GO silicon steel when the annealing temperature was 1,540 K.
基金the Advanced Research Fund for National Defense Science and Technology Key Laboratory(No.9104C3705021003)
文摘In order to conduct effective reliability analysis of retracting actuator with multi-state(success state,safety failure state and action failure state), we redefine type-3 operator in goal oriented(GO) method to describe three states of main charge of retracting actuator and improve type-15 operator in GO method to describe the logic relations of multi-state output. The quantitative and qualitative reliability analyses of retracting actuator are made based on GO method in this paper. The system state probability of retracting actuator is obtained through quantitative analysis, and its weakness is found through qualitative analysis. The analysis results show that GO method is effective to improve the reliability of retracting actuator, and this method is also feasible for reliability analysis of other complicated initiating explosive systems.
基金Technical Basis Projects of China's MIIT(Nos.ZQ092012B003,2012090003)
文摘Goal oriented( GO) methodology is a kind of success oriented system reliability analysis method and has been used widely.The repairable system with dual input closed-loop feedback link( DICLFL) considering shutdown correlation didn't make reliability analysis accurately based on existing GO methodology. So, a reliability analysis method used to deal with DICLFL considering shutdown correlation is provided based on GO methodology.Firstly, a new operator, which is used to describe DICLFL considering shutdown correlation,whose number is 1,is created and named as Type 9C operator. And then,the formulas of type 9C operator are derived based on Markov process theory. Finally,the new method presented in this paper is adopted to conduct the reliability analysis of an electro-hydraulic servo speed control system. The analysis result is compared with those of Monte Carlo simulation and fault tree analysis( FTA). The comparison results show that this new reliability analysis method based on GO methodology is feasible and meaningful for reliability analysis of repairable systems with DICLFL considering shutdown correlation.Meantime,it will be useful for more other applications.
基金National Natural Science Foundation of China (10477018) Science and Technology Innovation Foundation of North-western Polytechnical University (W016143)
文摘As an efficient artificial truncating boundary condition, conformal perfectly matched layer (CPML) is a kind of multilayer anisotropic absorbing media. To reduce computing effort of CPML, this article proposes a layer-oriented element integration algorithm. In this algorithm, the relative dielectric constant and permeability are considered as constants for each the very thin monolayer of CPML, and the element integration of multilayer along the normal direction is substituted by the element integration of m...
基金Project(50721003)supported by the Creative Research Group of National Natural Science Foundation of ChinaProject(50825102)supported by the National Science Fund for Distinguished Young Scholars,China
文摘A simple electrochemical method for the in situ preparation of homogeneously dispersed gold-polyaniline core/shell nanocomposite particles with controlled size on the highly oriented pyrolytic graphite(HOPG)was demonstrated.The HOPG surface was modified preferentially by covalent bonding of a two-dimensional 4-aminophenyl monolayer employing diazonium chemistry.AuCl4 -ions were attached to the Ar-NH2 termination and reduced electrochemically.This results in the formation of Au nuclei that could be further grown into gold nanoparticles.The formation of polyaniline as the shell wrap of Au nanoparticle was established by localized electro-polymerization.These core-shell nanocomposites prepared were characterized by AFM and cyclic voltammetry.The results show that the gold-polyaniline core-shell composites on HOPG have a mean particle size of 100 nm in diameter and the polyaniline shell thickness is about 15 nm.
基金National Natural Science Foundation of China(22078039)Science Fund for Creative Research Groups of the National Natural Science Foundation of China(22021005)+1 种基金National Key Research and Development Program of China(2023YFB3810700)the Fundamental Research Funds for the Central Universities(DUT22LAB602)。
文摘Preferential orientation control of metal—organic framework(MOF)films is advantageous for maximizing pore uniformity and minimizing grain-boundary defects.Nonetheless,the preparation of MOF films with both in-plane and out-of-plane orientations remains a grand challenge.In this study,we reported the preparation of three-dimensionally oriented MIL-96 layers through combining morphology control of MIL-96 seeds with addition of polyvinylpyrrolidone surfactants and arachidonic acids.The three-dimensionally oriented MIL-96 film was readily obtained through in-plane epitaxial growth.It is anticipated that the aforementioned protocol can be effective for obtaining diverse MOF films with a three-dimensionally oriented organization.
基金Supported by Henan Province Philosophy and Social Science Planning Project (2010FJJ045)Decision-making Project of Henan Provincial Government (2011B559)
文摘Based on the state governance background of peasant household oriented land circulation,I analyzed characteristics of peasant household oriented land circulation.The characteristics mainly include uncertain definition of rural land circulation,significant off-media feature of land circulation,long-term land circulation contract,farmers' preference of peasant household oriented land circulation,and progressive path of land circulation.The essential feature is the progressive mode of land circulation.Under the existing property right,it realizes the perfect combination of modern production factors and traditional agricultural,and the combination of traditional family safeguarding function and modern social mutual growth spirit.Thus,it shows relative independence and manifests the idea of common prosperity.The opportunity cost of peasant household oriented land circulation is minimal,institutional cost will increase circulation risk,and what's more,the cost for state governance of peasant household oriented land circulation is minimal.It comes to conclusion that building proper and harmonious land circulation mechanism is responsibility of central government and favorable for healthy development of peasant household oriented land circulation.
文摘Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.
基金financially supported by the National High Technology Research and Development Program of China(Grant No.2012AA03A505)
文摘In this study, high- and low-grade grain-oriented electrical steels were used as the initial materials to produce 0.08-mm-thick sheet with one-step cold-rolling method. Electron backscattering diffraction analysis technique and X-ray diffraction texture analysis technique were adopted to investigate the effect of initial Goss texture sharpness on texture evolution and magnetic properties of ultra-thin grain-oriented electrical steel. The results showed that primary recrystal- lization and secondary recrystallization were the main processes that occurred during annealing. The induced factors for secondary recrystallization of two grades samples were not Consistent. The high-grade samples presented texture induction mechanism, while the low-grade samples revealed strong surface-energy induction mechanism. The initial Goss texture sharpness had a great impact on texture evolution and magnetic properties of ultra-thin grain-oriented electrical steel. The Goss texture component formed after primary recrystallization was stronger, and better magnetic properties were obtained at low frequencies. For low-grade samples, secondary recrystallization enhanced the intensity of Goss texture, and both grain size and texture contributed to better high-frequency magnetic properties after secondary recrystallization. By controlling the annealing process, the magnetic properties of low-grade products could be significantly improved, thus achieving conversion from low-grade to high-grade products.
基金supported by the National Natural Science Foundation of China (Grant No.50871015)
文摘With the help of electron back scattering diffraction techniques and field emission microscope, the misorienta- tion and the precipitation environment of Goss grains in conventional grain-oriented steel were observed and investigated at the initial stage of secondary recrystallization. It reveals that the abnormal Goss grains have a high fraction of high angle boundaries ranging from 25 to 40 deg. The most important observation is that some of {110}〈001〉 grains in matrix indicated higher particle density than their neighbor grains during final annealing at 875℃ before secondary recrystallization, which could create a favorable environment for their abnormal grain growth. Based on misorientation and precipitation results, the abnormal growth mechanism of Goss grains was sketched.
基金supported by the Foundation of Guangxi Innovation Driven Development Project Grant(AA22068080)the Science and Technology Plan of Guangxi(No.ZY22096019,ZY20220101)+1 种基金the National Natural Science Foundation of China(No.52474431)the Research Plan of International Collaboration Fund for Creative Research Teams(ICFCRT)of NSFC(No.W2441008)。
文摘Inhibiting dendrites formation and side-reactions is a critical challenge for practical application of aqueous Zn-ion batteries(AZIBs).Electrolyte additives offer an effective solution to address this problem.Inspired by using green corrosion inhibitor for metals,we introduce caffeine,extracted from tea-leaf,as an additive to achieve stable AZIBs.Caffeine,with its N and O containing groups,strongly adsorbs on the Zn anode and Zn^(2+)ions.This featured adsorption induces the replacement of water molecules from electric double layer(EDL)and solvation shell,suppressing side-reactions such as corrosion and hydrogen evolution reaction(HER).Moreover,the selective adsorption and steric hindrance of caffeine promote Zn(002)-oriented deposition,resulting in uniform and compact zinc deposits at both low and high current density and areal capacity.Due to the significantly suppressed dendrites and corrosion,the Coulomb Efficiency(CE)reaches 99.24%after 800 cycles,and the Zn||MnO_(2)battery shows a specific capacity of 167.2 mAh g^(−1)with 81%capacity retention after 1000 cycles at 2 A g^(−1).
文摘After graduating from the China Academy of Arts(Department of Oil Painting)in Hangzhou in 1995,Yang Fudong(1971)moved to Shanghai to work as a graphic designer.Inspired by his daily job in Pudong,he started producing photographic series that closely resembled the advertising campaigns he worked on.Glossy images of stylish young people or dishevelled white collars in highly saturated colours,defined“intellectuals”in cryptic accompanying captions.Conversely,his body of work in black and white,almost entirely shot on 35mm film,portrays a suspended reality out of the historical time:a ghostly dimension akin to a drowsy vigil,a uchronia,an“estranged paradise”-to borrow the title of his earliest film set in Hangzhou.But it is Shanghai’s elusiveness and material relationship with the past that has contributed the most to form Yang’s trademark imagery and aesthetic.What he conjures up in his still and moving images,is a dimension with a distinctive oneiric quality,an“in-between”universe where all the circumstances are justified and have an inner logic,just like in dreams,or just like in the China of his childhood.The research of Yang Fudong is somewhat unique in the universe of contemporary Chinese art and sets him apart from a plethora of artists that have used the video in a much more“didactic”and quotational way.I will illustrate some specific aspects of his black and white body of work,trying to show how a certain self-orientalist trait can be interpreted as strategy to regain narrative agency and bring to the surface a series of removed instances:the main of which being,in my opinion,the fate of Shanghai’s(perhaps of China's Mainland in its ungraspable entirety?)modernity.
文摘Chinese consumers browsing e-commerce platforms or walking in supermarket aisles have noticed a new feature:dedicated sections for high-quality export products.Far from being a mere marketing gimmick,this trend emerged due to intense pressure from a slide in global demand.
基金supported by National Natural Science Foundation of China(52250010,52050128,52201242)the Natural Science Foundation of Jiangsu Province(BK20230086 and BK20240179).
文摘Cement occupies a significant proportion in construction,serving as the primary material for components such as bricks and walls.However,its role is largely limited to load-bearing functions,with little exploration of additional applications.Simultaneously,buildings remain a major contributor to global energy consumption,accounting for 40%of total energy use.Here,we for the first time endow cement with energy storage functionality by developing cement-based solid-state energy storage wallboards(CSESWs),which can utilize the ample idle surface areas of building walls to seamlessly store renewable energy from distributed photovoltaics without compromising building safety or requiring additional space.Owing to unprecedented microstructures and composition interactions,these CSESWs not only achieve a superionic conductivity of 101.1 mS cm^(−1)but also demonstrate multifunctionality,such as significant toughness,thermal insulation,lightweight,and adhesion.When integrated with asymmetrical electrodes,the CSESWs exhibit a remarkable capacitance(2778.9 mF cm^(−2))and high areal energy density(10.8 mWhcm^(−2)).Moreover,existing residential buildings renovated with our CSESWs can supply 98%of daily electricity needs,demonstrating their outstanding potential for realizing zero-carbon buildings.This study pioneers the use of cement in energy storage,providing a scalable and cost-effective pathway for sustainable construction.
基金supported by the National Natural Science Foundation of China(Grant Nos.52375348 and 52175331)the Natural Science Foundation of Shandong Province,China(Grant Nos.ZR2020ZD04 and ZR2022ME014).
文摘Flexible transparent antennas(FTAs)are widely used in wireless transmission fields,and their technological iterations are accelerating.However,the high losses caused by materials and structures limit the development of FTAs with both high light transmission and high gain,and the rapid iteration rate demands greater process flexibility,which makes it difficult for existing technologies to achieve both demands.Here,we design a novel shell-core structure composite metal mesh(CMM)FTA to achieve extremely low skin depth loss and ohmic loss using skin effect and report a novel hybrid additive manufacturing method based on electric field oriented deposition to achieve efficient and flexible manufacturing of the unique Ag/Cu core-shell structure CMM FTA.The typical sample has a light transmittance of 80%(including substrate)when the sheet resistance is 0.29Ω·sq^(-1),and has excellent bending and torsion resistance.The peak gain in the working band is as high as 5.22 dB,and the efficiency is 80%,which is close to the performance of the opaque Cu patch antenna.It also realizes smooth and stable real-time wireless transmission under bending and long-distance conditions.This method addresses the shortcomings of FTAs,namely their high cost,low manufacturing efficiency,and low performance,especially in the rapid iterative development of antennas.
基金Major Scientific Research Projects of China Railway Group(No.K2019G046)the National Key Research and Devel-opment Program of China(No.2020YFB1600700).
文摘Rail positioning is a critical step for detecting rail defects downstream.However,existing orientation-based detectors struggle to effectively manage rails with arbitrary inclinations and high aspect ratios,particularly in turnout sections.To address these challenges,a fuzzy boundary guidance and oriented Gaussian function-based anchor-free network termed the rail positioning network(RP-Net)is proposed for rail positioning in turnout sections.First,an oriented Gaussian function-based label generation strategy is introduced.This strategy produces smoother and more accu-rate label values by accounting for the specific aspect ratios and orientations of the rails.Second,a fuzzy boundary learning module is developed to enhance the network’s abil-ity to model the rail boundary regions effectively.Further-more,a boundary guidance module is developed to direct the network in fusing the features obtained from the downs-ampled network output with the boundary region features,which have been enhanced to contain more refined posi-tional and structural information.A local channel attention mechanism is integrated into this module to identify critical channels.Finally,experiments conducted on the tracking dataset show that the proposed RP-Net achieves high posi-tioning accuracy and demonstrates strong adaptability in complex scenarios.
基金supported by the Hong Kong Research Grants Council(No.CityU 11201522).
文摘The evolution of energy storage technology has seen remarkable progress,with a shift from pure metals to sophisticated,tailor-made active materials.The synthesis of nanostructures with exceptional properties is crucial in the advancement of electrode materials.In this regard,our study highlights the fabrication of a novel,oriented heterostructure comprised of Zn-Mn-Co-telluride grown on a pre-oxidized copper mesh using a hydrothermal method followed by a solvothermal process.This innovative approach leads to the formation of the Zn-Mn-Cotelluride@CuO@Cu heterostructure,which demonstrates the unique oriented morphology.It outperforms both Zn-Mn-Co-telluride@Cu and CuO@Cu by exhibiting lower electrical resistivity,increased redox activity,higher specific capacity,and improved ion diffusion characteristics.The conductivity enhancements of the heterostructure are corroborated by density functional theory(DFT)calculations.When utilized in a hybrid supercapacitor(HSC)alongside activated carbon(AC)electrodes,the Zn-Mn-Co-telluride@CuO@Cu heterostructurebased HSC achieves an energy density of 75.7 Wh kg^(-1).Such findings underscore the potential of these novel electrode materials to significantly impact the design of next-generation supercapacitor devices.
