A new method for determining proximity parameters α,β ,and η in electron beam lithography is introduced on the assumption that the point exposure spread function is composed of two Gaussians.A single line i...A new method for determining proximity parameters α,β ,and η in electron beam lithography is introduced on the assumption that the point exposure spread function is composed of two Gaussians.A single line is used as test pattern to determine proximity effect parameters and the normalization approach is adopted in experimental data transaction in order to eliminate the need of measuring exposure clearing dose of the resist.Furthermore,the parameters acquired by this method are successfully used for proximity effect correction in electron beam lithography on the same experimental conditions.展开更多
Utilizing small molecules as markers for specific cells or organs within biosystems is a crucial approach for studying and regulating physiological processes. However, current tagging strategies, due to the presence o...Utilizing small molecules as markers for specific cells or organs within biosystems is a crucial approach for studying and regulating physiological processes. However, current tagging strategies, due to the presence of exposed highly reactive groups, suffer from drawbacks such as low tagging efficiency or insufficient spatial specificity, thereby diminishing their expected effectiveness. Consequently, there is a pressing need to develop a strategy capable of in situ labeling of active groups in response to cellular or in vivo stimuli, ensuring both high tagging efficiency and spatial specificity. In this work, we devised a strategy for releasing aldehyde groups activated by hypochlorous acid(HOCl). Compounds synthesized through this strategy can release the fiuorophore methylene blue(MB) and aldehyde-based compounds upon HOCl activation. Given high reactivity of the released aldehyde group, it can effectively interact with macromolecules in biological systems, facilitating tagging and enabling prolonged imaging. To validate this concept, we further incorporated a naphthalimide structure with stable light emission to create SW-110. SW-110 can specifically respond to in vitro and endogenous HOCl, when release MB, it also releases naphthalimide fiuorophore with highly reactive aldehyde group for tagging within cells. This strategy provides a simple but efficient strategy for proximity tagging in situ.展开更多
Cilia are indispensable for organ development and function,and their dysfunction causes a range of syndromic diseases known as ciliopathies,including obesity,cystic kidney disease,situs inversus,and male infertility(R...Cilia are indispensable for organ development and function,and their dysfunction causes a range of syndromic diseases known as ciliopathies,including obesity,cystic kidney disease,situs inversus,and male infertility(Reiter and Leroux,2017;Wallmeier et al.,2020).To date,over 180 ciliopathy-associated genes have been identified(Reiter and Leroux,2017),yet the underlying mechanisms remain poorly understood.展开更多
Electrocatalytic conversion of nitrate to ammonia(NITRR)can simultaneously achieve the removal of nitrate and the synthesis of value-added ammonia,a promising candidate to replace Haber-Bosch process with low carbon d...Electrocatalytic conversion of nitrate to ammonia(NITRR)can simultaneously achieve the removal of nitrate and the synthesis of value-added ammonia,a promising candidate to replace Haber-Bosch process with low carbon dioxide emissions.However,high hydrogenation energy barrier for*NO intermediates and insufficient supply of active hydrogen cause slow hydrogenation process,and further result in low efficiency of nitrate conversion and ammonia synthesis.Herein,a series of tandem catalysts,one-dimensional coordination polymers(1D CCPs)with dual sites are synthesized and obtained 190.4 mg h^(-1)mgcat^(-1)ammonia production rate with Faradaic efficiency of 97.16%,outperforming to the most of recent reported catalysts.The catalytic performances are well-maintained even after a long-term stability test of 1200 h,laying the foundation for practical applications.Density functional theory results reveal that the stationary adsorbed*NO on Ni site induced proximity electronic effect could reduce the energy barrier for hydrogenation of*NO intermediates over Cu site.In addition,the Ni site in the dual sites 1D CCPs is conducive to generating active hydrogen,providing rich proton source to boost the hydrogenation of*NO,and further enhancing the compatibility of deoxygenation and hydrogenation process.Our work paves a new insight into the mechanism of NITRR process and will inspire more research interests in exploring the proximity electronic effect in catalytic process.展开更多
Acute lung injury(ALI)is a serious clinical condition with a high mortality rate.Oxidative stress and inflammatory responses play pivotal roles in the pathogenesis of ALI.ONOO^(−)is a key mediator that exacerbates oxi...Acute lung injury(ALI)is a serious clinical condition with a high mortality rate.Oxidative stress and inflammatory responses play pivotal roles in the pathogenesis of ALI.ONOO^(−)is a key mediator that exacerbates oxidative damage and microvascular permeability in ALI.Accurate detection of ONOO^(−)would facilitate early diagnosis and intervention in ALI.Near-infrared fluorescence(NIRF)probes offer new solutions due to their sensitivity,depth of tissue penetration,and imaging capabilities.However,the developed ONOO^(−)fluorescent probes face problems such as interference from other reactive oxygen species and easy intracellular diffusion.To address these issues,we introduced an innovative self-immobilizing NIRF probe,DCI2F-OTf,which was capable of monitoring ONOO^(−)in vitro and in vivo.Importantly,leveraging the high reactivity of the methylene quinone(QM)intermediate,DCI2F-OTf was able to covalently label proteins in the presence of ONOO^(−),enabling in situ imaging.In mice models of ALI,DCI2F-OTf enabled real-time imaging of ONOO^(−)levels and found that ONOO^(−)was tightly correlated with the progression of ALI.Our findings demonstrated that DCI2F-OTf was a promising chemical tool for the detection of ONOO^(−),which could help to gain insight into the pathogenesis of ALI and monitor treatment efficacy.展开更多
The development of single atom catalysts(SACs)with asymmetric active sites by defect regulation provides an encourage potential for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER),but highly challen...The development of single atom catalysts(SACs)with asymmetric active sites by defect regulation provides an encourage potential for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER),but highly challenging.Herein,N-doped carbon(N-C)anchored atomically dispersed Ni-N_(3)site with proximity defects(Ni-N_(3)D)induced by Te atoms doping is reported.Benefitting from the inductive effect of proximity defect,the Ni-N_(3)D/Te-N-C catalyst performs excellent ORR and HER performance in alkaline and acid condition.Both in situ characterization and theoretical calculation reveal that the existence of proximity defect effect is conducive to lower rate-determining-step energy barrier of ORR and HER,thus accelerating the multielectron reaction kinetics.This work paves a novel strategy for constructing highactivity bifunctional SACs by defect engineering for development of sustainable energy.展开更多
Ru-based nanomaterials have been demonstrated to be highly active electrocatalysts for hydrogen evo-lution reaction(HER),yet weak water adsorption and splitting ability in neutral media thus it is rather difficult for...Ru-based nanomaterials have been demonstrated to be highly active electrocatalysts for hydrogen evo-lution reaction(HER),yet weak water adsorption and splitting ability in neutral media thus it is rather difficult for the intermediates to adsorb on the active site.Herein,we introduce a concept of the prox-imity effect,com prising adjacent Ru and RuO_(2) nanoparticles coupled on TiO_(2)(Ru/RuO_(2)-TiO_(2)),for the synergic promotion of water molecule adsorption and splitting,significantly enhancing HER electrocatal-ysis performance.The in-situ spectroscopy experiments and density function theory(DFT)simulations demonstrated that the proximity effect between the adjacent Ru nanoparticles and RuO_(2) nanoparticles can accelerate water adsorption and splitting.As a result,the as-made Ru/RuO_(2)-TiO_(2) only need overpo-tentials of 52.7,16.0,and 16.4 mV to achieve the current density of 10 mA cm-2 in neutral,acid,and alkaline media,respectively.The mass activity of Ru/RuO_(2)-TiO_(2) in neutral media is 320 and 117 times higher than that of commercial Ru/C and Pt/C at the overpotential of 100 mV,respectively.This work emphasizes the proximity effect for activation of reactants which can be extended to other electrocat-alytic reactions.展开更多
Recently,electronic skins and fl exible wearable devices have been developed for widespread applications in medical monitoring,artifi cial intelligence,human–machine interaction,and artifi cial prosthetics.Flexible p...Recently,electronic skins and fl exible wearable devices have been developed for widespread applications in medical monitoring,artifi cial intelligence,human–machine interaction,and artifi cial prosthetics.Flexible proximity sensors can accurately perceive external objects without contact,introducing a new way to achieve an ultrasensitive perception of objects.This article reviews the progress of fl exible capacitive proximity sensors,fl exible triboelectric proximity sensors,and fl exible gate-enhanced proximity sensors,focusing on their applications in the electronic skin fi eld.Herein,their working mechanism,materials,preparation methods,and research progress are discussed in detail.Finally,we summarize the future challenges in developing fl exible proximity sensors.展开更多
Considering the efficiency and veracity of rules based optical proximity correction (OPC),the importance of rules in rules based OPC is pointed out.And how to select,to construct and to apply more concise and practi...Considering the efficiency and veracity of rules based optical proximity correction (OPC),the importance of rules in rules based OPC is pointed out.And how to select,to construct and to apply more concise and practical rules base is disscussed.Based on those ideas,four primary rules are suggested.Some data resulted in rules base are shown in table.The patterns on wafer are clearly improved by applying these rules to correct mask.OPCL,the automatic construction of the rules base is an important part of the whole rules based OPC system.展开更多
We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential...We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential routing. The routing algorithm is based on constructed force directed Steiner tree routing to enhance routing efficien- cy. Experimental results on industrial benchmark circuits show that the presented routing algorithm can obtain much improvement considering optical effects short runtime.展开更多
In order to analyze the electrostatic field concerned with electrostatic proximity fuze problem using the available finite analysis software package, the technology to model the problem with a scale reduction object a...In order to analyze the electrostatic field concerned with electrostatic proximity fuze problem using the available finite analysis software package, the technology to model the problem with a scale reduction object and boundary was presented. The boundary is determined by the maximum distance the sensor can detect. The object model is obtained by multiplying the terms in Poisson's equation with a scale reduction factor and the real value can be reconstructed with the same reverse process after software calculation. Using the finite element analysis program, the simulation value is close to the theoretical value with a little error. The boundary determination and scale reduction method is suitable to modeling the irregular electrostatic field around air targets, such as airplane, missile and so on, which is based on commonly used personal computer (PC). The technology reduces the calculation and storage cost greatly.展开更多
We describe the fabrication of metal nanogaps of sub-20nm in feature size using the proximity effect in electron beam lithography （EBL）. The proximity effect is extended to develop a flexible and practical method fo...We describe the fabrication of metal nanogaps of sub-20nm in feature size using the proximity effect in electron beam lithography （EBL）. The proximity effect is extended to develop a flexible and practical method for preparing metal （e. g. Au or Ag） nanogaps and arrays in combination with a transfer process （e. g., deposition/lift-off）. Different from the direct gap-writing process,the nanogap precursor structures （nanoconnections） were designed by GDSII software and then written by electron beam. Following a deposition and lift-off process, the metal nanogaps were obtained and the nanogap size can be lowered to -10nm by controlling the exposure dose in EBL.展开更多
Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects： qua...Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects： quafity, quantity, and advantage, measured by density, proximity, and accessibility indices. County is the basic unit for analysis. The results reveal： （1） Transport dominance statistically follows a partial normal distribution. A very few counties, 1.4% of the total, have extremely high transport dominance which strongly supports the socio-economic development in these areas. In contrast, one eighth of all counties have poor transport dominance which impedes local socio-economic development to some extent. The remaining areas, about 70% of the counties, have median transport dominance. （2） Transport dominance is spatially unevenly distributed, with values decreasing gradually from the coastal area to the inland area. Areas in the first-highest level of transport dominance are mainly concentrated in the Yangtze River Delta, the Greater Beijing area, and the Pearl River Delta. Areas in the second-highest level are focused in Chengdu, Chongqing, and Wuhan metropolitan areas. Provincial capitals and a few other counties belong to the third-highest level.展开更多
The rails of electromagnetic railgun can be ablated by the temperature rise due to current concentration.The current distributions on the rails and armature are not only affected by the skin effect,but also influenced...The rails of electromagnetic railgun can be ablated by the temperature rise due to current concentration.The current distributions on the rails and armature are not only affected by the skin effect,but also influenced by the proximity effect which is rarely mentioned.This paper illustrated the difference between skin effect and proximity effect,and the influencing factors of proximity effect were investigated.Results show that the current is concentrated on the surface around rails due to the skin effect,and the proximity effect exacerbates the current density on the inner surfaces of rails.Decrease in distance from rails enhances the proximity effect,but has nothing to do with the skin effect,which also augments the rail resistance,resulting in temperature rise.It can explain the reason why the ablation is often detected in the small caliber railgun.Research results in this paper can provide support for design and optimization of electromagnetic railgun.展开更多
High resolution Fresnel zone plates for nanoscale three-dimensional imaging of materials by both soft and hard x-rays are increasingly needed by the broad applications in nanoscience and nanotechnology.When the outmos...High resolution Fresnel zone plates for nanoscale three-dimensional imaging of materials by both soft and hard x-rays are increasingly needed by the broad applications in nanoscience and nanotechnology.When the outmost zone-width is shrinking down to 50 nm or even below,patterning the zone plates with high aspect ratio by electron beam lithography still remains a challenge because of the proximity effect.The uneven charge distribution in the exposed resist is still frequently observed even after standard proximity effect correction(PEC),because of the large variety in the line width.This work develops a new strategy,nicknamed as local proximity effect correction(LPEC),efficiently modifying the deposited energy over the whole zone plate on the top of proximity effect correction.By this way,50 nm zone plates with the aspect ratio from 4:1 up to 15:1 and the duty cycle close to 0.5 have been fabricated.Their imaging capability in soft(1.3 keV)and hard(9 keV)x-ray,respectively,has been demonstrated in Shanghai Synchrotron Radiation Facility(SSRF)with the resolution of 50 nm.The local proximity effect correction developed in this work should also be generally significant for the generation of zone plates with high resolutions beyond 50 nm.展开更多
The formation maintenance of multiple unmanned aerial vehicles(UAVs)based on proximity behavior is explored in this study.Individual decision-making is conducted according to the expected UAV formation structure and t...The formation maintenance of multiple unmanned aerial vehicles(UAVs)based on proximity behavior is explored in this study.Individual decision-making is conducted according to the expected UAV formation structure and the position,velocity,and attitude information of other UAVs in the azimuth area.This resolves problems wherein nodes are necessarily strongly connected and communication is strictly consistent under the traditional distributed formation control method.An adaptive distributed formation flight strategy is established for multiple UAVs by exploiting proximity behavior observations,which remedies the poor flexibility in distributed formation.This technique ensures consistent position and attitude among UAVs.In the proposed method,the azimuth area relative to the UAV itself is established to capture the state information of proximal UAVs.The dependency degree factor is introduced to state update equation based on proximity behavior.Finally,the formation position,speed,and attitude errors are used to form an adaptive dynamic adjustment strategy.Simulations are conducted to demonstrate the effectiveness and robustness of the theoretical results,thus validating the effectiveness of the proposed method.展开更多
Topographic feature points and lines are the framework of topography,and their spatial distance relationship is an breakthrough in the study of topographical geometry,internal structure and development level.Proximity...Topographic feature points and lines are the framework of topography,and their spatial distance relationship is an breakthrough in the study of topographical geometry,internal structure and development level.Proximity distance(PD)is an indicator to describe the distance between the gully source point(GSP)and the watershed boundary.In the upstream catchment area,PDs can be expressed by the streamline proximity distance(SPD),as well as by the horizontal proximity distance(HPD)and the vertical proximity distance(VPD)in the horizontal and vertical dimensions,respectively.The series of indicators(e.g.,SPD,HPD and VPD)are important for quantifying the geomorphological development process of a loess basin because of the headward erosion of loess gullies.In this study,the digital elevation model data with 5 m resolution and a digital topographic analysis method are used for the statistical analyses of the SPD,VPD and HPD in 50 sample areas of 6 geomorphic types in the Loess Plateau of northern Shaanxi.The spatial characteristics and the influencing factors are also analysed.Results show that:1)Central tendencies for the HPDs and the VPDs for the whole study area and the six typical loess landforms are evident.2)Spatial patterns of the HPDs and the VPDs exhibit evident trends and zonal distributions over the whole study area.3)The HPDs have a strong positive correlation with gully density(GD)and hypsometric integral.The VPDs also correlates with GD to an extent.Vegetation cover,mean annual precipitation and loess thickness have stronger effects on the VPD than on the HPD.展开更多
文摘A new method for determining proximity parameters α,β ,and η in electron beam lithography is introduced on the assumption that the point exposure spread function is composed of two Gaussians.A single line is used as test pattern to determine proximity effect parameters and the normalization approach is adopted in experimental data transaction in order to eliminate the need of measuring exposure clearing dose of the resist.Furthermore,the parameters acquired by this method are successfully used for proximity effect correction in electron beam lithography on the same experimental conditions.
基金financially supported by the National Natural Science Foundation of China (Nos. 22177019, 22377010, 22371038)State Key Laboratory for Modification of Chemical Fibers and Polymer Materials (No. KF2206)。
文摘Utilizing small molecules as markers for specific cells or organs within biosystems is a crucial approach for studying and regulating physiological processes. However, current tagging strategies, due to the presence of exposed highly reactive groups, suffer from drawbacks such as low tagging efficiency or insufficient spatial specificity, thereby diminishing their expected effectiveness. Consequently, there is a pressing need to develop a strategy capable of in situ labeling of active groups in response to cellular or in vivo stimuli, ensuring both high tagging efficiency and spatial specificity. In this work, we devised a strategy for releasing aldehyde groups activated by hypochlorous acid(HOCl). Compounds synthesized through this strategy can release the fiuorophore methylene blue(MB) and aldehyde-based compounds upon HOCl activation. Given high reactivity of the released aldehyde group, it can effectively interact with macromolecules in biological systems, facilitating tagging and enabling prolonged imaging. To validate this concept, we further incorporated a naphthalimide structure with stable light emission to create SW-110. SW-110 can specifically respond to in vitro and endogenous HOCl, when release MB, it also releases naphthalimide fiuorophore with highly reactive aldehyde group for tagging within cells. This strategy provides a simple but efficient strategy for proximity tagging in situ.
基金supported by grants from the National Key Research and Development Program of China(2019YFA0802704)the National Natural Science Foundation of China(31771620)+2 种基金the Natural Science Foundation of Chongqing,China(CSTB2022NSCQMSX1424)Research Startup Fund of Southwest University(SWU117064)Open Research Fund of National Health Commission Key Laboratory of Birth Defects Prevention&Henan Key Laboratory of Population Defects Prevention(ZD202302)。
文摘Cilia are indispensable for organ development and function,and their dysfunction causes a range of syndromic diseases known as ciliopathies,including obesity,cystic kidney disease,situs inversus,and male infertility(Reiter and Leroux,2017;Wallmeier et al.,2020).To date,over 180 ciliopathy-associated genes have been identified(Reiter and Leroux,2017),yet the underlying mechanisms remain poorly understood.
文摘Electrocatalytic conversion of nitrate to ammonia(NITRR)can simultaneously achieve the removal of nitrate and the synthesis of value-added ammonia,a promising candidate to replace Haber-Bosch process with low carbon dioxide emissions.However,high hydrogenation energy barrier for*NO intermediates and insufficient supply of active hydrogen cause slow hydrogenation process,and further result in low efficiency of nitrate conversion and ammonia synthesis.Herein,a series of tandem catalysts,one-dimensional coordination polymers(1D CCPs)with dual sites are synthesized and obtained 190.4 mg h^(-1)mgcat^(-1)ammonia production rate with Faradaic efficiency of 97.16%,outperforming to the most of recent reported catalysts.The catalytic performances are well-maintained even after a long-term stability test of 1200 h,laying the foundation for practical applications.Density functional theory results reveal that the stationary adsorbed*NO on Ni site induced proximity electronic effect could reduce the energy barrier for hydrogenation of*NO intermediates over Cu site.In addition,the Ni site in the dual sites 1D CCPs is conducive to generating active hydrogen,providing rich proton source to boost the hydrogenation of*NO,and further enhancing the compatibility of deoxygenation and hydrogenation process.Our work paves a new insight into the mechanism of NITRR process and will inspire more research interests in exploring the proximity electronic effect in catalytic process.
基金supported by the National Natural Science Foundation of China(Nos.22264013,21961010)Hainan Province Science and Technology Special Fund(Nos.ZDYF2021SHFZ219,ZDYF2022SHFZ037)+4 种基金Special Funds of S&T Cooperation and Exchange Projects of Shanxi Province(No.202204041101040)Natural Science Research Talent Project of Hainan Medical University(No.JBGS202101)Postgraduate Innovative Research Project of Hainan(No.Qhys2021-384)Hainan Province Clinical Medical Center(2021)Project for Functional Materials and Molecular Imaging Science Innovation Group of Hainan Medical University.
文摘Acute lung injury(ALI)is a serious clinical condition with a high mortality rate.Oxidative stress and inflammatory responses play pivotal roles in the pathogenesis of ALI.ONOO^(−)is a key mediator that exacerbates oxidative damage and microvascular permeability in ALI.Accurate detection of ONOO^(−)would facilitate early diagnosis and intervention in ALI.Near-infrared fluorescence(NIRF)probes offer new solutions due to their sensitivity,depth of tissue penetration,and imaging capabilities.However,the developed ONOO^(−)fluorescent probes face problems such as interference from other reactive oxygen species and easy intracellular diffusion.To address these issues,we introduced an innovative self-immobilizing NIRF probe,DCI2F-OTf,which was capable of monitoring ONOO^(−)in vitro and in vivo.Importantly,leveraging the high reactivity of the methylene quinone(QM)intermediate,DCI2F-OTf was able to covalently label proteins in the presence of ONOO^(−),enabling in situ imaging.In mice models of ALI,DCI2F-OTf enabled real-time imaging of ONOO^(−)levels and found that ONOO^(−)was tightly correlated with the progression of ALI.Our findings demonstrated that DCI2F-OTf was a promising chemical tool for the detection of ONOO^(−),which could help to gain insight into the pathogenesis of ALI and monitor treatment efficacy.
基金financially supported by the National Natural Science Foundation of China(22478432,22108306,22178388)Taishan Scholars Program of Shandong Province(tsqn201909065)+2 种基金Shandong Provincial Natural Science Foundation(ZR2024JQ004)Innovation Fund Project for Graduate Student of China University of Petroleum(East China)the Fundamental Research Funds for the Central Universities(No.25CX04020A)。
文摘The development of single atom catalysts(SACs)with asymmetric active sites by defect regulation provides an encourage potential for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER),but highly challenging.Herein,N-doped carbon(N-C)anchored atomically dispersed Ni-N_(3)site with proximity defects(Ni-N_(3)D)induced by Te atoms doping is reported.Benefitting from the inductive effect of proximity defect,the Ni-N_(3)D/Te-N-C catalyst performs excellent ORR and HER performance in alkaline and acid condition.Both in situ characterization and theoretical calculation reveal that the existence of proximity defect effect is conducive to lower rate-determining-step energy barrier of ORR and HER,thus accelerating the multielectron reaction kinetics.This work paves a novel strategy for constructing highactivity bifunctional SACs by defect engineering for development of sustainable energy.
基金supported by the Young Project of the Education Department in Guizhou Province(No.2022099)the Natural Science Special of Guizhou University(No.X202220 Special Post A).
文摘Ru-based nanomaterials have been demonstrated to be highly active electrocatalysts for hydrogen evo-lution reaction(HER),yet weak water adsorption and splitting ability in neutral media thus it is rather difficult for the intermediates to adsorb on the active site.Herein,we introduce a concept of the prox-imity effect,com prising adjacent Ru and RuO_(2) nanoparticles coupled on TiO_(2)(Ru/RuO_(2)-TiO_(2)),for the synergic promotion of water molecule adsorption and splitting,significantly enhancing HER electrocatal-ysis performance.The in-situ spectroscopy experiments and density function theory(DFT)simulations demonstrated that the proximity effect between the adjacent Ru nanoparticles and RuO_(2) nanoparticles can accelerate water adsorption and splitting.As a result,the as-made Ru/RuO_(2)-TiO_(2) only need overpo-tentials of 52.7,16.0,and 16.4 mV to achieve the current density of 10 mA cm-2 in neutral,acid,and alkaline media,respectively.The mass activity of Ru/RuO_(2)-TiO_(2) in neutral media is 320 and 117 times higher than that of commercial Ru/C and Pt/C at the overpotential of 100 mV,respectively.This work emphasizes the proximity effect for activation of reactants which can be extended to other electrocat-alytic reactions.
基金supported by the National Key R&D Program of China(Nos.2022 YFF 1202700 and 2022YFB3203500)National Natural Science Foundation of China(Nos.62225403,62375046,51973024,an d U19A2091)+2 种基金“111”Project(No.B13013)Natur al Sci ence Foundation of Jilin Pro vin ce(No.20230101113JC)the Funding from Jilin Pr ovince(No.20220502002GH).
文摘Recently,electronic skins and fl exible wearable devices have been developed for widespread applications in medical monitoring,artifi cial intelligence,human–machine interaction,and artifi cial prosthetics.Flexible proximity sensors can accurately perceive external objects without contact,introducing a new way to achieve an ultrasensitive perception of objects.This article reviews the progress of fl exible capacitive proximity sensors,fl exible triboelectric proximity sensors,and fl exible gate-enhanced proximity sensors,focusing on their applications in the electronic skin fi eld.Herein,their working mechanism,materials,preparation methods,and research progress are discussed in detail.Finally,we summarize the future challenges in developing fl exible proximity sensors.
文摘Considering the efficiency and veracity of rules based optical proximity correction (OPC),the importance of rules in rules based OPC is pointed out.And how to select,to construct and to apply more concise and practical rules base is disscussed.Based on those ideas,four primary rules are suggested.Some data resulted in rules base are shown in table.The patterns on wafer are clearly improved by applying these rules to correct mask.OPCL,the automatic construction of the rules base is an important part of the whole rules based OPC system.
文摘We present a detailed routing algorithm considering the optical proximity effect. The light intensity is calculated beforehand and stored in look-up tables. These costs are used as a constraint to guide the sequential routing. The routing algorithm is based on constructed force directed Steiner tree routing to enhance routing efficien- cy. Experimental results on industrial benchmark circuits show that the presented routing algorithm can obtain much improvement considering optical effects short runtime.
文摘In order to analyze the electrostatic field concerned with electrostatic proximity fuze problem using the available finite analysis software package, the technology to model the problem with a scale reduction object and boundary was presented. The boundary is determined by the maximum distance the sensor can detect. The object model is obtained by multiplying the terms in Poisson's equation with a scale reduction factor and the real value can be reconstructed with the same reverse process after software calculation. Using the finite element analysis program, the simulation value is close to the theoretical value with a little error. The boundary determination and scale reduction method is suitable to modeling the irregular electrostatic field around air targets, such as airplane, missile and so on, which is based on commonly used personal computer (PC). The technology reduces the calculation and storage cost greatly.
基金the National Natural Science Foundation of China(No.20704042)the Shanghai Pujiang Talent Plan(No.07PJ14095)+1 种基金the CAS Knowledge Innovation Programthe Committee of Science and Technology of Shanghai(Nos.06XD14020,07JC14058,0752nm016)~~
文摘We describe the fabrication of metal nanogaps of sub-20nm in feature size using the proximity effect in electron beam lithography （EBL）. The proximity effect is extended to develop a flexible and practical method for preparing metal （e. g. Au or Ag） nanogaps and arrays in combination with a transfer process （e. g., deposition/lift-off）. Different from the direct gap-writing process,the nanogap precursor structures （nanoconnections） were designed by GDSII software and then written by electron beam. Following a deposition and lift-off process, the metal nanogaps were obtained and the nanogap size can be lowered to -10nm by controlling the exposure dose in EBL.
基金National Natural Science Foundation of China, No.40635026 40701045 Knowledge Innovation Program of the Chinese Academy of Sciences, No.KZCX2-YW-Q 10-4
文摘Transport infrastructure plays an important role in shaping the configuration of spatial socio-economic structures and influences regional accessibility. This paper defines transport dominance from three aspects： quafity, quantity, and advantage, measured by density, proximity, and accessibility indices. County is the basic unit for analysis. The results reveal： （1） Transport dominance statistically follows a partial normal distribution. A very few counties, 1.4% of the total, have extremely high transport dominance which strongly supports the socio-economic development in these areas. In contrast, one eighth of all counties have poor transport dominance which impedes local socio-economic development to some extent. The remaining areas, about 70% of the counties, have median transport dominance. （2） Transport dominance is spatially unevenly distributed, with values decreasing gradually from the coastal area to the inland area. Areas in the first-highest level of transport dominance are mainly concentrated in the Yangtze River Delta, the Greater Beijing area, and the Pearl River Delta. Areas in the second-highest level are focused in Chengdu, Chongqing, and Wuhan metropolitan areas. Provincial capitals and a few other counties belong to the third-highest level.
文摘The rails of electromagnetic railgun can be ablated by the temperature rise due to current concentration.The current distributions on the rails and armature are not only affected by the skin effect,but also influenced by the proximity effect which is rarely mentioned.This paper illustrated the difference between skin effect and proximity effect,and the influencing factors of proximity effect were investigated.Results show that the current is concentrated on the surface around rails due to the skin effect,and the proximity effect exacerbates the current density on the inner surfaces of rails.Decrease in distance from rails enhances the proximity effect,but has nothing to do with the skin effect,which also augments the rail resistance,resulting in temperature rise.It can explain the reason why the ablation is often detected in the small caliber railgun.Research results in this paper can provide support for design and optimization of electromagnetic railgun.
基金Project supported by the National Natural Science Foundation of China(Grant No.U1732104)China Postdoctoral Science Foundation(Grant No.2017M611443)Shanghai STCSM2019-11-20 Grant,China(Grant No.19142202700)。
文摘High resolution Fresnel zone plates for nanoscale three-dimensional imaging of materials by both soft and hard x-rays are increasingly needed by the broad applications in nanoscience and nanotechnology.When the outmost zone-width is shrinking down to 50 nm or even below,patterning the zone plates with high aspect ratio by electron beam lithography still remains a challenge because of the proximity effect.The uneven charge distribution in the exposed resist is still frequently observed even after standard proximity effect correction(PEC),because of the large variety in the line width.This work develops a new strategy,nicknamed as local proximity effect correction(LPEC),efficiently modifying the deposited energy over the whole zone plate on the top of proximity effect correction.By this way,50 nm zone plates with the aspect ratio from 4:1 up to 15:1 and the duty cycle close to 0.5 have been fabricated.Their imaging capability in soft(1.3 keV)and hard(9 keV)x-ray,respectively,has been demonstrated in Shanghai Synchrotron Radiation Facility(SSRF)with the resolution of 50 nm.The local proximity effect correction developed in this work should also be generally significant for the generation of zone plates with high resolutions beyond 50 nm.
文摘The formation maintenance of multiple unmanned aerial vehicles(UAVs)based on proximity behavior is explored in this study.Individual decision-making is conducted according to the expected UAV formation structure and the position,velocity,and attitude information of other UAVs in the azimuth area.This resolves problems wherein nodes are necessarily strongly connected and communication is strictly consistent under the traditional distributed formation control method.An adaptive distributed formation flight strategy is established for multiple UAVs by exploiting proximity behavior observations,which remedies the poor flexibility in distributed formation.This technique ensures consistent position and attitude among UAVs.In the proposed method,the azimuth area relative to the UAV itself is established to capture the state information of proximal UAVs.The dependency degree factor is introduced to state update equation based on proximity behavior.Finally,the formation position,speed,and attitude errors are used to form an adaptive dynamic adjustment strategy.Simulations are conducted to demonstrate the effectiveness and robustness of the theoretical results,thus validating the effectiveness of the proposed method.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41871288, 41930102 and 41602182)the Fundamental Research Funds for the Central Universities (Grant No. 2018CSLZ002)
文摘Topographic feature points and lines are the framework of topography,and their spatial distance relationship is an breakthrough in the study of topographical geometry,internal structure and development level.Proximity distance(PD)is an indicator to describe the distance between the gully source point(GSP)and the watershed boundary.In the upstream catchment area,PDs can be expressed by the streamline proximity distance(SPD),as well as by the horizontal proximity distance(HPD)and the vertical proximity distance(VPD)in the horizontal and vertical dimensions,respectively.The series of indicators(e.g.,SPD,HPD and VPD)are important for quantifying the geomorphological development process of a loess basin because of the headward erosion of loess gullies.In this study,the digital elevation model data with 5 m resolution and a digital topographic analysis method are used for the statistical analyses of the SPD,VPD and HPD in 50 sample areas of 6 geomorphic types in the Loess Plateau of northern Shaanxi.The spatial characteristics and the influencing factors are also analysed.Results show that:1)Central tendencies for the HPDs and the VPDs for the whole study area and the six typical loess landforms are evident.2)Spatial patterns of the HPDs and the VPDs exhibit evident trends and zonal distributions over the whole study area.3)The HPDs have a strong positive correlation with gully density(GD)and hypsometric integral.The VPDs also correlates with GD to an extent.Vegetation cover,mean annual precipitation and loess thickness have stronger effects on the VPD than on the HPD.
