We are delighted to introduce this Special Issue of Acta Metallurgica Sinica(English Letters)dedicated to"Thermoelectric Materials and Devices."Thermoelectric materials and devices have emerged as a promisin...We are delighted to introduce this Special Issue of Acta Metallurgica Sinica(English Letters)dedicated to"Thermoelectric Materials and Devices."Thermoelectric materials and devices have emerged as a promising technology for sustainable energy solutions,enabling efficient conversion between heat and electricity.This special collection highlights the latest advancements in the field,showcasing cutting-edge research and fostering interdisciplinary collaboration among researchers worldwide.展开更多
All-optical analog-to-digital conversion (ADC) has been extensively researched to break through the inherently limited operating speed of electronic devices. In this paper, we use the photonic crystal fiber (PCF) for ...All-optical analog-to-digital conversion (ADC) has been extensively researched to break through the inherently limited operating speed of electronic devices. In this paper, we use the photonic crystal fiber (PCF) for time-stretch (TS) analog-to-digital (A/D) conversion system through generating low noise, linear chirp distribution and flat super-continuum (SC). Based on the radio frequency (RF) analog signal modulated to the linearly chirped super-continuum, the large-dispersion photonic crystal fiber is used for time-domain stretching.展开更多
Piezoelectric transduction technology enables the direct conversion between mechanical and electrical energy,finding extensive applications in sensing,acoustics,imaging,actuation,and energy harvesting[1].Previous stud...Piezoelectric transduction technology enables the direct conversion between mechanical and electrical energy,finding extensive applications in sensing,acoustics,imaging,actuation,and energy harvesting[1].Previous studies on piezoelectric materials have primarily focused on ceramics or single-crystal materials characterized by wide band gaps(E_(g)>2.0 e V[2])and low electrical conductivity.In contrast,narrow-bandgap(E_(g)<0.5 eV[3])semiconductor materials typically exhibit high electrical conductivity,which is unfavorable for the effective accumulation of charges required to establish a stable voltage response.Consequently,experimental investigations into the piezoelectric effect of narrow-bandgap semiconductors are scarce.展开更多
The effect of In composition on two-dimensional electron gas in wurtzite AlGaN/InGaN heterostructures is theoretically investigated. The sheet carrier density is shown to increase nearly linearly with In mole fraction...The effect of In composition on two-dimensional electron gas in wurtzite AlGaN/InGaN heterostructures is theoretically investigated. The sheet carrier density is shown to increase nearly linearly with In mole fraction x, due to the increase in the polarization charge at the AlGaN/InGaN interface. The electron sheet density is enhanced with the doping in the AlGaN layer. The sheet carrier density is as high as 3.7×1013 cm^-2 at the donor density of 10×1018 cm^-3 for the HEMT structure with x=0.3. The contribution of additional donor density on the electron sheet density is nearly independent of the In mole fraction.展开更多
Various metal-based electrocatalysts from nanocrystals,to clusters and single-atoms,have been well-discovered towards high-efficient power devices and electrocatalytic conversion.To accelerate energy transformation ma...Various metal-based electrocatalysts from nanocrystals,to clusters and single-atoms,have been well-discovered towards high-efficient power devices and electrocatalytic conversion.To accelerate energy transformation materials discovery,developing high-throughput DFT calculations and machine-learning techniques is of great necessity.This review comprehensively outlines the latest progress of theory-guided design of advanced energy transformation materials.Especially,we focus on the study of single atoms in various power devices,such as fuel cell(oxygen reduction reaction,ORR;acid oxidation reaction;alcohol oxidation reaction),and other reactions for energy-related electrocatalytic conversion of small molecules,such as H_(2)O_(2)evolution reactions(2e−ORR),water splitting(H_(2)evolution reaction/O_(2)evolution reaction,HER/OER),N2 reduction reaction(NRR),and CO_(2)reduction reactions(CO_(2)RR).Firstly,the electronic structure,interaction mechanism,and reaction activation path are discussed to provide an overall blueprint in electrocatalysis and batteries mentioned above.Thereafter,the experimental synthesis strategies,structural recognition,and electrocatalytic performance for the advanced energy transformation materials are figured out.Finally,some viewpoints into the current issues and future design concept of the advanced energy transformation materials are provided.展开更多
Two-dimensional(2D)materials offer novel platforms to meet the increasing demands of next-generation miniaturized electronics.Among them,the recently emerged 2D Bi_(2)O_(2)Se with unique non-van der Waals interlayer i...Two-dimensional(2D)materials offer novel platforms to meet the increasing demands of next-generation miniaturized electronics.Among them,the recently emerged 2D Bi_(2)O_(2)Se with unique non-van der Waals interlayer interaction,high mobility,sizeable bandgap,and capability to fabricate homologous heterojunction,is of particular interest.In this Review,we introduce recent progress in preparation,transfer,mechanical and electrical properties,and electronic applications of 2D Bi_(2)O_(2)Se.First,we summarize methodologies to synthesize and massively produce 2D Bi_(2)O_(2)Se,as well as recent advances in transferring them from growth substrate to arbitrary substrates.Then,we review current understandings on the intrinsic mechanical properties of Bi_(2)O_(2)Se at 2D thickness limit,and its in-plane and out-of-plane electrical properties.Electronic devices including field-effect transistors,memristors,and sensors based on 2D Bi_(2)O_(2)Se for neuromorphic computing,memory,logic,and integrated circuits are discussed.Finally,challenges and prospects for the development of 2D Bi_(2)O_(2)Se are proposed.展开更多
背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,...背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,同时综述可能的作用机制。方法:通过检索Pub Med和中国知网数据库,收集截至2024年3月的相关文献,英文检索词:“stem cells,direct current electric field,pulsed electric field,migration,electric field device,mechanism”;中文检索词:“干细胞,直流电场,脉冲电场,迁移,电场装置,机制”。排除不能获取全文和与主题无关的文献。结果与结论:根据筛选要求共纳入58篇文献,包括中文文献15篇及英文文献43篇。文献以脂肪间充质干细胞、骨髓间充质干细胞、神经干细胞、表皮干细胞、人胚胎干细胞和人诱导性多功能干细胞为研究对象,在迁移装置中研究电场的不同参数对上述干细胞迁移的影响及其机制。(1)电场作为一种简单、无创且稳定的干预方式在指导干细胞定向迁移的过程中起着积极作用;(2)不同类型的干细胞发生趋电性迁移的方向不同,同时大部分干细胞的迁移速度和定向性是随着电场强度增加而增加的;(3)不同的电场装置在观测干细胞迁移时的侧重点不同,可根据实验目的而择优选择相关装置;(4)不同干细胞趋电性迁移的机制不完全相同,多数干细胞迁移过程中有MAPK通路、ROCK活化以及PI3K功能的参与,同时还有其他蛋白质复合物与信号通路参与调控该过程;(5)除电场参数不同之外,细胞本身的衰老情况和培养环境也会对趋电性迁移的结果产生影响。总而言之,电场作为一种影响干细胞迁移特性的重要信号,与其他新兴材料结合在组织工程应用中展现出了一定的潜力,有望在指导干细胞归巢方面发挥更加重要的作用,促进骨组织再生和修复以及神经系统、自身免疫系统以及肿瘤等疾病的研究取得更大的突破。展开更多
文摘We are delighted to introduce this Special Issue of Acta Metallurgica Sinica(English Letters)dedicated to"Thermoelectric Materials and Devices."Thermoelectric materials and devices have emerged as a promising technology for sustainable energy solutions,enabling efficient conversion between heat and electricity.This special collection highlights the latest advancements in the field,showcasing cutting-edge research and fostering interdisciplinary collaboration among researchers worldwide.
基金supported by the Doctoral Program of Higher Education Research Fund (No.1101.01.001.672)
文摘All-optical analog-to-digital conversion (ADC) has been extensively researched to break through the inherently limited operating speed of electronic devices. In this paper, we use the photonic crystal fiber (PCF) for time-stretch (TS) analog-to-digital (A/D) conversion system through generating low noise, linear chirp distribution and flat super-continuum (SC). Based on the radio frequency (RF) analog signal modulated to the linearly chirped super-continuum, the large-dispersion photonic crystal fiber is used for time-domain stretching.
文摘Piezoelectric transduction technology enables the direct conversion between mechanical and electrical energy,finding extensive applications in sensing,acoustics,imaging,actuation,and energy harvesting[1].Previous studies on piezoelectric materials have primarily focused on ceramics or single-crystal materials characterized by wide band gaps(E_(g)>2.0 e V[2])and low electrical conductivity.In contrast,narrow-bandgap(E_(g)<0.5 eV[3])semiconductor materials typically exhibit high electrical conductivity,which is unfavorable for the effective accumulation of charges required to establish a stable voltage response.Consequently,experimental investigations into the piezoelectric effect of narrow-bandgap semiconductors are scarce.
文摘The effect of In composition on two-dimensional electron gas in wurtzite AlGaN/InGaN heterostructures is theoretically investigated. The sheet carrier density is shown to increase nearly linearly with In mole fraction x, due to the increase in the polarization charge at the AlGaN/InGaN interface. The electron sheet density is enhanced with the doping in the AlGaN layer. The sheet carrier density is as high as 3.7×1013 cm^-2 at the donor density of 10×1018 cm^-3 for the HEMT structure with x=0.3. The contribution of additional donor density on the electron sheet density is nearly independent of the In mole fraction.
基金supported by the National Key R&D Program of China(2018YFA0702003)the National Natural Science Foundation of China(21890383,21871159)+1 种基金the Science and Technology Key Project of Guangdong Province of China(2020B010188002)the China Postdoctoral Science Foundation(2021M691834).
文摘Various metal-based electrocatalysts from nanocrystals,to clusters and single-atoms,have been well-discovered towards high-efficient power devices and electrocatalytic conversion.To accelerate energy transformation materials discovery,developing high-throughput DFT calculations and machine-learning techniques is of great necessity.This review comprehensively outlines the latest progress of theory-guided design of advanced energy transformation materials.Especially,we focus on the study of single atoms in various power devices,such as fuel cell(oxygen reduction reaction,ORR;acid oxidation reaction;alcohol oxidation reaction),and other reactions for energy-related electrocatalytic conversion of small molecules,such as H_(2)O_(2)evolution reactions(2e−ORR),water splitting(H_(2)evolution reaction/O_(2)evolution reaction,HER/OER),N2 reduction reaction(NRR),and CO_(2)reduction reactions(CO_(2)RR).Firstly,the electronic structure,interaction mechanism,and reaction activation path are discussed to provide an overall blueprint in electrocatalysis and batteries mentioned above.Thereafter,the experimental synthesis strategies,structural recognition,and electrocatalytic performance for the advanced energy transformation materials are figured out.Finally,some viewpoints into the current issues and future design concept of the advanced energy transformation materials are provided.
基金We acknowledge support from the Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110980)the National Natural Science Foundation of China(Nos.51991343,51991340,52188101,and 52102179)+3 种基金the National Science Fund for Distinguished Young Scholars(No.52125309)Guangdong Innovative and Entrepreneurial Research Team Program(No.2017ZT07C341)the Bureau of Industry and Information Technology of Shenzhen for the“2017 Graphene Manufacturing Innovation Center Project”(No.201901171523)the Shenzhen Basic Research Program(No.JCYJ20200109144616617)。
文摘Two-dimensional(2D)materials offer novel platforms to meet the increasing demands of next-generation miniaturized electronics.Among them,the recently emerged 2D Bi_(2)O_(2)Se with unique non-van der Waals interlayer interaction,high mobility,sizeable bandgap,and capability to fabricate homologous heterojunction,is of particular interest.In this Review,we introduce recent progress in preparation,transfer,mechanical and electrical properties,and electronic applications of 2D Bi_(2)O_(2)Se.First,we summarize methodologies to synthesize and massively produce 2D Bi_(2)O_(2)Se,as well as recent advances in transferring them from growth substrate to arbitrary substrates.Then,we review current understandings on the intrinsic mechanical properties of Bi_(2)O_(2)Se at 2D thickness limit,and its in-plane and out-of-plane electrical properties.Electronic devices including field-effect transistors,memristors,and sensors based on 2D Bi_(2)O_(2)Se for neuromorphic computing,memory,logic,and integrated circuits are discussed.Finally,challenges and prospects for the development of 2D Bi_(2)O_(2)Se are proposed.
文摘背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,同时综述可能的作用机制。方法:通过检索Pub Med和中国知网数据库,收集截至2024年3月的相关文献,英文检索词:“stem cells,direct current electric field,pulsed electric field,migration,electric field device,mechanism”;中文检索词:“干细胞,直流电场,脉冲电场,迁移,电场装置,机制”。排除不能获取全文和与主题无关的文献。结果与结论:根据筛选要求共纳入58篇文献,包括中文文献15篇及英文文献43篇。文献以脂肪间充质干细胞、骨髓间充质干细胞、神经干细胞、表皮干细胞、人胚胎干细胞和人诱导性多功能干细胞为研究对象,在迁移装置中研究电场的不同参数对上述干细胞迁移的影响及其机制。(1)电场作为一种简单、无创且稳定的干预方式在指导干细胞定向迁移的过程中起着积极作用;(2)不同类型的干细胞发生趋电性迁移的方向不同,同时大部分干细胞的迁移速度和定向性是随着电场强度增加而增加的;(3)不同的电场装置在观测干细胞迁移时的侧重点不同,可根据实验目的而择优选择相关装置;(4)不同干细胞趋电性迁移的机制不完全相同,多数干细胞迁移过程中有MAPK通路、ROCK活化以及PI3K功能的参与,同时还有其他蛋白质复合物与信号通路参与调控该过程;(5)除电场参数不同之外,细胞本身的衰老情况和培养环境也会对趋电性迁移的结果产生影响。总而言之,电场作为一种影响干细胞迁移特性的重要信号,与其他新兴材料结合在组织工程应用中展现出了一定的潜力,有望在指导干细胞归巢方面发挥更加重要的作用,促进骨组织再生和修复以及神经系统、自身免疫系统以及肿瘤等疾病的研究取得更大的突破。
