Smart farming with outdoor monitoring systems is critical to address food shortages and sustainability challenges.These systems facilitate informed decisions that enhance efficiency in broader environmental management...Smart farming with outdoor monitoring systems is critical to address food shortages and sustainability challenges.These systems facilitate informed decisions that enhance efficiency in broader environmental management.Existing outdoor systems equipped with energy harvesters and self-powered sensors often struggle with fluctuating energy sources,low durability under harsh conditions,non-transparent or non-biocompatible materials,and complex structures.Herein,a multifunctional hydrogel is developed,which can fulfill all the above requirements and build selfsustainable outdoor monitoring systems solely by it.It can serve as a stable energy harvester that continuously generates direct current output with an average power density of 1.9 W m^(-3)for nearly 60 days of operation in normal environments(24℃,60%RH),with an energy density of around 1.36×10^(7)J m^(-3).It also shows good self-recoverability in severe environments(45℃,30%RH)in nearly 40 days of continuous operation.Moreover,this hydrogel enables noninvasive and self-powered monitoring of leaf relative water content,providing critical data on evaluating plant health,previously obtainable only through invasive or high-power consumption methods.Its potential extends to acting as other self-powered environmental sensors.This multifunctional hydrogel enables self-sustainable outdoor systems with scalable and low-cost production,paving the way for future agriculture.展开更多
The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic ...The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic material and renewable energy-generated electricity drive the conversion of carbon dioxide into high-value chemicals and carbon-neutral fuels.Over the past few years,single-atom catalysts have been intensively studied as they could provide near-unity atom utilization and unique catalytic performance.Single-atom catalysts have become one of the state-of-the-art catalyst materials for the electrochemical reduction of carbon dioxide into carbon monoxide.However,it remains a challenge for single-atom catalysts to facilitate the efficient conversion of carbon dioxide into products beyond carbon monoxide.In this review,we summarize and present important findings and critical insights from studies on the electrochemical carbon dioxide reduction reaction into hydrocarbons and oxygenates using single-atom catalysts.It is hoped that this review gives a thorough recapitulation and analysis of the science behind the catalysis of carbon dioxide into more reduced products through singleatom catalysts so that it can be a guide for future research and development on catalysts with industry-ready performance for the electrochemical reduction of carbon dioxide into high-value chemicals and carbon-neutral fuels.展开更多
Heterogeneous iron-based catalysts have drawn increasing attention in the advanced oxidation of persulfates due to their abundance in nature,the lack of secondary pollution to the environment,and their low cost over t...Heterogeneous iron-based catalysts have drawn increasing attention in the advanced oxidation of persulfates due to their abundance in nature,the lack of secondary pollution to the environment,and their low cost over the last a few years.In this paper,the latest progress in the research on the activation of persulfate by heterogeneous iron-based catalysts is reviewed from two aspects,in terms of synthesized catalysts(Fe0,Fe_(2)O_(3),Fe_(3)O_(4),FeOOH)and natural iron ore catalysts(pyrite,magnetite,hematite,siderite,goethite,ferrohydrite,ilmenite and lepidocrocite)focusing on efforts made to improve the performance of catalysts.The advantages and disadvantages of the synthesized catalysts and natural iron ore were summarized.Particular interests were paid to the activation mechanisms in the catalyst/PS/pollutant system for removal of organic pollutants.Future research challenges in the context of field application were also discussed.展开更多
针对基于共线方程的模型在实际应用中的限制,研究并探索用于航天影像解算的有理函数模型(rational function model,RFM),以及它在航空影像中的解算有效性。从模型的定义、模型的性质以及模型的求解等方面对RFM给出了系统性的解释,并分析...针对基于共线方程的模型在实际应用中的限制,研究并探索用于航天影像解算的有理函数模型(rational function model,RFM),以及它在航空影像中的解算有效性。从模型的定义、模型的性质以及模型的求解等方面对RFM给出了系统性的解释,并分析了RFM拟合光束法平差的精度。本文以基于共线方程的光束法空中三角测量平差成果为参照依据,比较分析了有理函数模型拟合光束法模型的相对精度。结果表明有理函数模型能以较高精度拟合光束法模型,有能力代替基于严格共线方程的经典模型以完成空中三角测量等任务。本文为RFM在无人机等近景影像中的应用提供了理论借鉴。展开更多
Atmospheric corrosion of metals is the most common type of corrosion which has a significant impact on the environment and operational safety in various situations of everyday life.Some of the common examples can be o...Atmospheric corrosion of metals is the most common type of corrosion which has a significant impact on the environment and operational safety in various situations of everyday life.Some of the common examples can be observed in land,water and air transportation systems,electronic circuit boards,urban and offshore infrastructures.The dew drops formed on metal surface due to condensation of atmospheric moisture facilitates corrosion as an electrolyte.The corrosion mechanisms under these droplets are different from classically known bulk electrolyte corrosion.Due to thin and non-uniform geometric thickness of the droplet electrolyte,the atmospheric oxygen requires a shorter diffusion path to reach the metal surface.The corrosion under a droplet is driven by the depletion of oxygen in the center of the droplet compared to the edge,known as differential aeration.In case of a larger droplet,differential aeration leads to preferential cathodic activity at the edge and is controlled by the droplet geometry.Whereas,for a smaller droplet,the oxygen concentration remains uniform and hence cathodic activity is not controlled by droplet geometry.The geometry of condensed droplets varies dynamically with changing environmental parameters,influencing corrosion mechanisms as the droplets evolve in size.In this review,various modelling approaches used to simulate the corrosion under droplet electrolytes are presented.In the efforts of developing a comprehensive model to estimate corrosion rates,it has been noted from this review that the influence of geometric evolution of the droplet due to condensation/evaporation processes on corrosion mechanisms are yet to be modelled.Dynamically varying external factors like environmental temperature,relative humidity,presence of hygroscopic salts and pollutants influence the evolution of droplet electrolyte,making it a complex phenomenon to investigate.Therefore,an overview of available dropwise condensation and evaporation models which describes the formation and the evolution of droplet geometry are also presented from an atmo s pheric corrosion viewpoint.展开更多
当前,民用市场中中小企业和家庭视频监控规模呈爆发式增长,针对上千万摄像机的监控需求,产业界普遍采用点对点(peer to peer,P2P)网络视频监控技术,综合阐述了P2P网络视频监控技术原理,分析了主流的P2P网络视频监控所采用的流媒体控制...当前,民用市场中中小企业和家庭视频监控规模呈爆发式增长,针对上千万摄像机的监控需求,产业界普遍采用点对点(peer to peer,P2P)网络视频监控技术,综合阐述了P2P网络视频监控技术原理,分析了主流的P2P网络视频监控所采用的流媒体控制技术、传输技术以及私网穿越技术,最后提出了大规模部署的P2P视频监控解决方案建议。展开更多
基金supported by the Research Platform for biomedical and Health Technology, NUS (Suzhou) Research Institute (RP-BHT-Prof. LEE Chengkuo)RIE Advanced Manufacturing and Engineering (AME) Programmatic Grant (Grant A18A4b0055)+1 种基金RIE 2025-Industry Alignment Fund – Industry Collaboration Projects (IAF-ICP) (Grant I2301E0027)Reimagine Research Scheme projects, National University of Singapore, A-0009037-03-00 and A-0009454-01-00 and Reimagine Research Scheme projects, National University of Singapore, A-0004772-00-00 and A-0004772-01-00。
文摘Smart farming with outdoor monitoring systems is critical to address food shortages and sustainability challenges.These systems facilitate informed decisions that enhance efficiency in broader environmental management.Existing outdoor systems equipped with energy harvesters and self-powered sensors often struggle with fluctuating energy sources,low durability under harsh conditions,non-transparent or non-biocompatible materials,and complex structures.Herein,a multifunctional hydrogel is developed,which can fulfill all the above requirements and build selfsustainable outdoor monitoring systems solely by it.It can serve as a stable energy harvester that continuously generates direct current output with an average power density of 1.9 W m^(-3)for nearly 60 days of operation in normal environments(24℃,60%RH),with an energy density of around 1.36×10^(7)J m^(-3).It also shows good self-recoverability in severe environments(45℃,30%RH)in nearly 40 days of continuous operation.Moreover,this hydrogel enables noninvasive and self-powered monitoring of leaf relative water content,providing critical data on evaluating plant health,previously obtainable only through invasive or high-power consumption methods.Its potential extends to acting as other self-powered environmental sensors.This multifunctional hydrogel enables self-sustainable outdoor systems with scalable and low-cost production,paving the way for future agriculture.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIP)(NRF,2021R1C1C1013953,2022K1A4A7A04094394,2022K1A4A7A04095890)。
文摘The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic material and renewable energy-generated electricity drive the conversion of carbon dioxide into high-value chemicals and carbon-neutral fuels.Over the past few years,single-atom catalysts have been intensively studied as they could provide near-unity atom utilization and unique catalytic performance.Single-atom catalysts have become one of the state-of-the-art catalyst materials for the electrochemical reduction of carbon dioxide into carbon monoxide.However,it remains a challenge for single-atom catalysts to facilitate the efficient conversion of carbon dioxide into products beyond carbon monoxide.In this review,we summarize and present important findings and critical insights from studies on the electrochemical carbon dioxide reduction reaction into hydrocarbons and oxygenates using single-atom catalysts.It is hoped that this review gives a thorough recapitulation and analysis of the science behind the catalysis of carbon dioxide into more reduced products through singleatom catalysts so that it can be a guide for future research and development on catalysts with industry-ready performance for the electrochemical reduction of carbon dioxide into high-value chemicals and carbon-neutral fuels.
基金supported by the National Natural Science Foundation of China(No.52170071)the Natural Science Foundation of Guangdong Province(No.2022A1515011909)the Natural Science Foundation of Xiamen(No.3502Z20227187).
文摘Heterogeneous iron-based catalysts have drawn increasing attention in the advanced oxidation of persulfates due to their abundance in nature,the lack of secondary pollution to the environment,and their low cost over the last a few years.In this paper,the latest progress in the research on the activation of persulfate by heterogeneous iron-based catalysts is reviewed from two aspects,in terms of synthesized catalysts(Fe0,Fe_(2)O_(3),Fe_(3)O_(4),FeOOH)and natural iron ore catalysts(pyrite,magnetite,hematite,siderite,goethite,ferrohydrite,ilmenite and lepidocrocite)focusing on efforts made to improve the performance of catalysts.The advantages and disadvantages of the synthesized catalysts and natural iron ore were summarized.Particular interests were paid to the activation mechanisms in the catalyst/PS/pollutant system for removal of organic pollutants.Future research challenges in the context of field application were also discussed.
文摘针对基于共线方程的模型在实际应用中的限制,研究并探索用于航天影像解算的有理函数模型(rational function model,RFM),以及它在航空影像中的解算有效性。从模型的定义、模型的性质以及模型的求解等方面对RFM给出了系统性的解释,并分析了RFM拟合光束法平差的精度。本文以基于共线方程的光束法空中三角测量平差成果为参照依据,比较分析了有理函数模型拟合光束法模型的相对精度。结果表明有理函数模型能以较高精度拟合光束法模型,有能力代替基于严格共线方程的经典模型以完成空中三角测量等任务。本文为RFM在无人机等近景影像中的应用提供了理论借鉴。
基金financially supported by the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie grant agreement(No.764977)。
文摘Atmospheric corrosion of metals is the most common type of corrosion which has a significant impact on the environment and operational safety in various situations of everyday life.Some of the common examples can be observed in land,water and air transportation systems,electronic circuit boards,urban and offshore infrastructures.The dew drops formed on metal surface due to condensation of atmospheric moisture facilitates corrosion as an electrolyte.The corrosion mechanisms under these droplets are different from classically known bulk electrolyte corrosion.Due to thin and non-uniform geometric thickness of the droplet electrolyte,the atmospheric oxygen requires a shorter diffusion path to reach the metal surface.The corrosion under a droplet is driven by the depletion of oxygen in the center of the droplet compared to the edge,known as differential aeration.In case of a larger droplet,differential aeration leads to preferential cathodic activity at the edge and is controlled by the droplet geometry.Whereas,for a smaller droplet,the oxygen concentration remains uniform and hence cathodic activity is not controlled by droplet geometry.The geometry of condensed droplets varies dynamically with changing environmental parameters,influencing corrosion mechanisms as the droplets evolve in size.In this review,various modelling approaches used to simulate the corrosion under droplet electrolytes are presented.In the efforts of developing a comprehensive model to estimate corrosion rates,it has been noted from this review that the influence of geometric evolution of the droplet due to condensation/evaporation processes on corrosion mechanisms are yet to be modelled.Dynamically varying external factors like environmental temperature,relative humidity,presence of hygroscopic salts and pollutants influence the evolution of droplet electrolyte,making it a complex phenomenon to investigate.Therefore,an overview of available dropwise condensation and evaporation models which describes the formation and the evolution of droplet geometry are also presented from an atmo s pheric corrosion viewpoint.
文摘当前,民用市场中中小企业和家庭视频监控规模呈爆发式增长,针对上千万摄像机的监控需求,产业界普遍采用点对点(peer to peer,P2P)网络视频监控技术,综合阐述了P2P网络视频监控技术原理,分析了主流的P2P网络视频监控所采用的流媒体控制技术、传输技术以及私网穿越技术,最后提出了大规模部署的P2P视频监控解决方案建议。