Against the backdrop of increasingly prominent global energy shortages and environmental issues,the development of efficient energy conversion and storage technologies has become crucial.Zero-dimensional(0D)metal oxid...Against the backdrop of increasingly prominent global energy shortages and environmental issues,the development of efficient energy conversion and storage technologies has become crucial.Zero-dimensional(0D)metal oxide composites exhibit significant application value in the field of energy chemistry due to their unique properties,such as quantum size effect and high specific surface area.From a broad perspective,this paper reviews the main synthesis methods of these composites,including sol-gel method,hydrothermal/solvothermal method,precipitation method,and template method,while analyzing the characteristics of each method.It further discusses their applications in photocatalytic hydrogen production,fuel cells,lithium-ion batteries,and supercapacitors.Additionally,the current challenges,such as material dispersibility and interface bonding,are pointed out,and future development directions are prospected,aiming to provide references for related research.展开更多
In this article,we conduct a study on mixed quasi-martingale Hardy spaces that are defined by means of the mixed L_(p)-norm.By utilizing Doob’s inequalities,we explore the atomic decomposition and quasi-martingale in...In this article,we conduct a study on mixed quasi-martingale Hardy spaces that are defined by means of the mixed L_(p)-norm.By utilizing Doob’s inequalities,we explore the atomic decomposition and quasi-martingale inequalities of mixed quasi-martingale Hardy spaces.Moreover,we furnish sufficient conditions for the boundedness ofσ-sublinear operators in these spaces.These findings extend the existing conclusions regarding mixed quasi-martingale Hardy spaces defined with the help of the mixed L_(p)-norm.展开更多
随着全球供应链的日益复杂化和不确定性增加,提升供应链韧性成为我国面临的重要挑战。本文基于Web of Science数据库和知网数据库,结合可视化分析方法,对2013—2024年国内外供应链韧性领域相关文献进行对比分析,研究结果表明:(1)国内研...随着全球供应链的日益复杂化和不确定性增加,提升供应链韧性成为我国面临的重要挑战。本文基于Web of Science数据库和知网数据库,结合可视化分析方法,对2013—2024年国内外供应链韧性领域相关文献进行对比分析,研究结果表明:(1)国内研究起步晚于国外,且发文量少于国外。国外整体合作密切程度强于国内,国内、国外均未形成核心作者群。(2)国内相关研究主要集中在技术创新对供应链韧性的影响、供应链韧性战略以及供应链韧性评价等方面;国外相关研究主要集中在供应链韧性内涵、供应链韧性作用机制、供应链韧性评估模型等方面。(3)国内研究演进脉络分为两个阶段,国外研究演进脉络分为三个阶段。(4)在研究前沿方面,国内现阶段聚焦数字化方面,反映了产业升级需求;国外现阶段侧重于数字化与地缘政治方面。展开更多
Sensitive and reliable X-ray detectors are essential for medical radiography,industrial inspection and security screening.Lowering the radiation dose allows reduced health risks and increased frequency and fidelity of...Sensitive and reliable X-ray detectors are essential for medical radiography,industrial inspection and security screening.Lowering the radiation dose allows reduced health risks and increased frequency and fidelity of diagnostic technologies for earlier detection of disease and its recurrence.Three-dimensional(3 D)organic-inorganic hybrid lead halide perovskites are promising for direct X-ray detection-they show improved sensitivity compared to conventional X-ray detectors.However,their high and unstable dark current,caused by ion migration and high dark carrier concentration in the 3 D hybrid perovskites,limits their performance and long-term operation stability.Here we report ultrasensitive,stable X-ray detectors made using zero-dimensional(0 D)methylammonium bismuth iodide perovskite(MA3Bi2I9)single crystals.The 0 D crystal structure leads to a high activation energy(Ea)for ion migration(0.46 e V)and is also accompanied by a low dark carrier concentration(~10^6 cm^-3).The X-ray detectors exhibit sensitivity of 10,620μC Gy-1 air cm-2,a limit of detection(Lo D)of 0.62 nG yairs-1,and stable operation even under high applied biases;no deterioration in detection performance was observed following sensing of an integrated X-ray irradiation dose of^23,800 m Gyair,equivalent to>200,000 times the dose required for a single commercial X-ray chest radiograph.Regulating the ion migration channels and decreasing the dark carrier concentration in perovskites provide routes for stable and ultrasensitive X-ray detectors.展开更多
Zero-dimensional(0D)hybrid metal halides,which consist of organic cations and isolated inorganic metal halide anions,have emerged as phosphors with efficient broadband emissions.However,these materials generally have ...Zero-dimensional(0D)hybrid metal halides,which consist of organic cations and isolated inorganic metal halide anions,have emerged as phosphors with efficient broadband emissions.However,these materials generally have too wide bandgaps and thus cannot be excited by blue light,which hinders their applications for efficient white light-emitting diodes(WLEDs).The key to achieving a blue-light-excitable 0D hybrid metal halide phosphor is to reduce the fundamental bandgap by rational chemical design.In this work,we report two designed hybrid copper(I)iodides,(Ph_(3)MeP)_(2)Cu_(4)I_(6)and(Cy_(3)MeP)_(2)Cu_(4)I_(6),as blue-light-excitable yellow phosphors with ultrabroadband emission.In these compounds,the[Cu_(4)I_(6)]^(2-)anion forms an I6 octahedron centered on a cationic Cu_(4)tetrahedron.The strong cation-cation bonding within the unique cationic Cu_(4)tetrahedra enables significantly lowered conduction band minimums and thus narrowed bandgaps,as compared to other reported hybrid copper(I)iodides.The ultrabroadband emission is attributed to the coexistence of free and self-trapped excitons.The WLED using the[Cu_(4)I_(6)]^(2-)anion-based single phosphor shows warm white light emission,with a high luminous efficiency of 65 Im W^(-1)and a high color rendering index of 88.This work provides strategies to design narrow-bandgap 0D hybrid metal halides and presents two first examples of blue-light-excitable 0D hybrid metal halide phosphors for efficient WLEDs.展开更多
本文基于知识图谱理论,选取1986—2024年中国知网(CNKI)收录的1072篇中文文献为样本,并辅以Web of Science核心合集中的英文文献,运用CiteSpace和VOSviewer软件,从发文数量、研究机构、载文期刊、关键词突现、时间演进与聚类等维度,对...本文基于知识图谱理论,选取1986—2024年中国知网(CNKI)收录的1072篇中文文献为样本,并辅以Web of Science核心合集中的英文文献,运用CiteSpace和VOSviewer软件,从发文数量、研究机构、载文期刊、关键词突现、时间演进与聚类等维度,对制造业转型研究的演化脉络和热点主题进行系统梳理。研究发现:制造业转型相关文献数量持续增长,呈现出显著的多学科交叉特征;研究主题经历了从早期的价值链优化,逐步拓展至数字化、绿色化、智能化与服务化等多个路径;近年来,研究重点进一步聚焦于企业绩效、人才培养与国际竞争力等议题。整体来看,制造业转型正由要素驱动向数字技术主导、多路径融合演进。本文研究成果可为理论拓展与政策制定提供系统参考。展开更多
小麦赤霉病研究对于农业生产和保障全球粮食安全具有重要意义。为深入了解小麦赤霉病研究进展和动态前沿,运用CiteSpace软件,对近20年来Web of Science核心合集中1236篇小麦赤霉病研究文献进行系统分析。结果表明,近20年来小麦赤霉病研...小麦赤霉病研究对于农业生产和保障全球粮食安全具有重要意义。为深入了解小麦赤霉病研究进展和动态前沿,运用CiteSpace软件,对近20年来Web of Science核心合集中1236篇小麦赤霉病研究文献进行系统分析。结果表明,近20年来小麦赤霉病研究发文量总体呈上升趋势,美国以345篇的发文量位居榜首,中美、中英、中加等国际合作网络较为紧密。研究内容主要集中在病原菌特性、病害防治技术、抗病品种选育等方面;当前研究热点以抗病性鉴定、分子标记辅助选择、新型生物防治剂开发等为主;热门技术方法涉及分子代谢组学、基因组学、遥感监测技术等。展望未来,小麦赤霉病研究将更加注重跨学科合作,致力于开发高效、环保的病害防控策略,以应对全球粮食安全挑战。展开更多
文摘Against the backdrop of increasingly prominent global energy shortages and environmental issues,the development of efficient energy conversion and storage technologies has become crucial.Zero-dimensional(0D)metal oxide composites exhibit significant application value in the field of energy chemistry due to their unique properties,such as quantum size effect and high specific surface area.From a broad perspective,this paper reviews the main synthesis methods of these composites,including sol-gel method,hydrothermal/solvothermal method,precipitation method,and template method,while analyzing the characteristics of each method.It further discusses their applications in photocatalytic hydrogen production,fuel cells,lithium-ion batteries,and supercapacitors.Additionally,the current challenges,such as material dispersibility and interface bonding,are pointed out,and future development directions are prospected,aiming to provide references for related research.
基金Supported by the National Natural Science Foundation of China(11871195)。
文摘In this article,we conduct a study on mixed quasi-martingale Hardy spaces that are defined by means of the mixed L_(p)-norm.By utilizing Doob’s inequalities,we explore the atomic decomposition and quasi-martingale inequalities of mixed quasi-martingale Hardy spaces.Moreover,we furnish sufficient conditions for the boundedness ofσ-sublinear operators in these spaces.These findings extend the existing conclusions regarding mixed quasi-martingale Hardy spaces defined with the help of the mixed L_(p)-norm.
文摘随着全球供应链的日益复杂化和不确定性增加,提升供应链韧性成为我国面临的重要挑战。本文基于Web of Science数据库和知网数据库,结合可视化分析方法,对2013—2024年国内外供应链韧性领域相关文献进行对比分析,研究结果表明:(1)国内研究起步晚于国外,且发文量少于国外。国外整体合作密切程度强于国内,国内、国外均未形成核心作者群。(2)国内相关研究主要集中在技术创新对供应链韧性的影响、供应链韧性战略以及供应链韧性评价等方面;国外相关研究主要集中在供应链韧性内涵、供应链韧性作用机制、供应链韧性评估模型等方面。(3)国内研究演进脉络分为两个阶段,国外研究演进脉络分为三个阶段。(4)在研究前沿方面,国内现阶段聚焦数字化方面,反映了产业升级需求;国外现阶段侧重于数字化与地缘政治方面。
基金supported by the National Natural Science Foundation of China(Grant nos.21773218,61974063)the Sichuan Province(Grant no.2018JY0206)the China Academy of Engineering Physics(Grant no.YZJJLX2018007)。
文摘Sensitive and reliable X-ray detectors are essential for medical radiography,industrial inspection and security screening.Lowering the radiation dose allows reduced health risks and increased frequency and fidelity of diagnostic technologies for earlier detection of disease and its recurrence.Three-dimensional(3 D)organic-inorganic hybrid lead halide perovskites are promising for direct X-ray detection-they show improved sensitivity compared to conventional X-ray detectors.However,their high and unstable dark current,caused by ion migration and high dark carrier concentration in the 3 D hybrid perovskites,limits their performance and long-term operation stability.Here we report ultrasensitive,stable X-ray detectors made using zero-dimensional(0 D)methylammonium bismuth iodide perovskite(MA3Bi2I9)single crystals.The 0 D crystal structure leads to a high activation energy(Ea)for ion migration(0.46 e V)and is also accompanied by a low dark carrier concentration(~10^6 cm^-3).The X-ray detectors exhibit sensitivity of 10,620μC Gy-1 air cm-2,a limit of detection(Lo D)of 0.62 nG yairs-1,and stable operation even under high applied biases;no deterioration in detection performance was observed following sensing of an integrated X-ray irradiation dose of^23,800 m Gyair,equivalent to>200,000 times the dose required for a single commercial X-ray chest radiograph.Regulating the ion migration channels and decreasing the dark carrier concentration in perovskites provide routes for stable and ultrasensitive X-ray detectors.
基金financially supported by the National Natural Science Foundation of China(Grant No.51972130)the Startup Fund of Huazhong University of Science and Technologythe Director Fund of Wuhan National Laboratory for Optoelectronics
文摘Zero-dimensional(0D)hybrid metal halides,which consist of organic cations and isolated inorganic metal halide anions,have emerged as phosphors with efficient broadband emissions.However,these materials generally have too wide bandgaps and thus cannot be excited by blue light,which hinders their applications for efficient white light-emitting diodes(WLEDs).The key to achieving a blue-light-excitable 0D hybrid metal halide phosphor is to reduce the fundamental bandgap by rational chemical design.In this work,we report two designed hybrid copper(I)iodides,(Ph_(3)MeP)_(2)Cu_(4)I_(6)and(Cy_(3)MeP)_(2)Cu_(4)I_(6),as blue-light-excitable yellow phosphors with ultrabroadband emission.In these compounds,the[Cu_(4)I_(6)]^(2-)anion forms an I6 octahedron centered on a cationic Cu_(4)tetrahedron.The strong cation-cation bonding within the unique cationic Cu_(4)tetrahedra enables significantly lowered conduction band minimums and thus narrowed bandgaps,as compared to other reported hybrid copper(I)iodides.The ultrabroadband emission is attributed to the coexistence of free and self-trapped excitons.The WLED using the[Cu_(4)I_(6)]^(2-)anion-based single phosphor shows warm white light emission,with a high luminous efficiency of 65 Im W^(-1)and a high color rendering index of 88.This work provides strategies to design narrow-bandgap 0D hybrid metal halides and presents two first examples of blue-light-excitable 0D hybrid metal halide phosphors for efficient WLEDs.
文摘本文基于知识图谱理论,选取1986—2024年中国知网(CNKI)收录的1072篇中文文献为样本,并辅以Web of Science核心合集中的英文文献,运用CiteSpace和VOSviewer软件,从发文数量、研究机构、载文期刊、关键词突现、时间演进与聚类等维度,对制造业转型研究的演化脉络和热点主题进行系统梳理。研究发现:制造业转型相关文献数量持续增长,呈现出显著的多学科交叉特征;研究主题经历了从早期的价值链优化,逐步拓展至数字化、绿色化、智能化与服务化等多个路径;近年来,研究重点进一步聚焦于企业绩效、人才培养与国际竞争力等议题。整体来看,制造业转型正由要素驱动向数字技术主导、多路径融合演进。本文研究成果可为理论拓展与政策制定提供系统参考。
文摘小麦赤霉病研究对于农业生产和保障全球粮食安全具有重要意义。为深入了解小麦赤霉病研究进展和动态前沿,运用CiteSpace软件,对近20年来Web of Science核心合集中1236篇小麦赤霉病研究文献进行系统分析。结果表明,近20年来小麦赤霉病研究发文量总体呈上升趋势,美国以345篇的发文量位居榜首,中美、中英、中加等国际合作网络较为紧密。研究内容主要集中在病原菌特性、病害防治技术、抗病品种选育等方面;当前研究热点以抗病性鉴定、分子标记辅助选择、新型生物防治剂开发等为主;热门技术方法涉及分子代谢组学、基因组学、遥感监测技术等。展望未来,小麦赤霉病研究将更加注重跨学科合作,致力于开发高效、环保的病害防控策略,以应对全球粮食安全挑战。
