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一种角向传输线B-dot标定平台的设计
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作者 张信军 罗维熙 +2 位作者 呼义翔 尹佳辉 周文渊 《强激光与粒子束》 CAS CSCD 北大核心 2024年第5期9-14,共6页
基于感应电压叠加器感应腔角向传输线电流探头离线标定的需求,设计了离线标定平台。离线标定平台为平板传输线结构,与在线标定相比,对标定信号的畸变更低。分析了跨平台标定误差的来源,并针对性提出降低误差的措施。分析表明,安装偏心... 基于感应电压叠加器感应腔角向传输线电流探头离线标定的需求,设计了离线标定平台。离线标定平台为平板传输线结构,与在线标定相比,对标定信号的畸变更低。分析了跨平台标定误差的来源,并针对性提出降低误差的措施。分析表明,安装偏心及探头纵向安装深度是跨平台标定误差的最大来源,需要在工程设计中重点关注。实际建立了离线标定平台并开展误差分析,得到跨平台标定误差3.3%的结果。 展开更多
关键词 感应腔 角向传输线 B-dot 标定
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Clinical features and possible pathogenesis of multiple evanescent white dot syndrome with different retinal diseases and events:a narrative review
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作者 Chun-Li Chen Yi-Zhe Cheng +2 位作者 Zhi-Han Zhang Ge Wang Xiao-Yan Peng 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期583-595,共13页
●Multiple evanescent white dot syndrome(MEWDS)is a rare fundus disease,characterized by acute vision loss and visual field defects.Many previous studies have explained the possible pathogenesis and clinical features ... ●Multiple evanescent white dot syndrome(MEWDS)is a rare fundus disease,characterized by acute vision loss and visual field defects.Many previous studies have explained the possible pathogenesis and clinical features of primary MEWDS.However,as the number of reported cases increases,secondary MEWDS occurs in other related retinal diseases and injuries,exhibiting some special characteristics.The associated retinal diseases include multifocal choroiditis/punctate inner choroidopathy(MFC/PIC),acute zonal occult outer retinopathy,best vitelliform macular dystrophy,pseudoxanthoma elasticum,and ocular toxoplasmosis.The related retinal injury is laser photocoagulation,surgery,and trauma.Although primary MEWDS often have a self-limiting course,secondary MEWDS may require treatment in some cases,according to the severity of concomitant diseases and complications.Notably,MEWDS secondary to MFC/PIC that is prone to forming choroidal neovascularization and focal choroidal excavation,needs positive treatment with corticosteroids.The possible underlying pathogenesis of secondary MEWDS is the exposure of choroidal antigen after the disruption of Bruch’s membrane.The MEWDS-related features in secondary MEWDS are still evanescent under most circumstances.Its prognosis and treatment depend on the severity of complications.Current studies propose that the etiology is associated with immune factors,including viral infection,inflammation in choroid and Bruch’s membrane,and antigen exposure caused by retinal and/or choroidal insults.More pathogenic studies should be conducted in the future.Accurate diagnosis for secondary MEWDS could benefit patients in aspects of management and prognosis. 展开更多
关键词 multiple evanescent white dot syndrome punctate inner choroidopathy multifocal choroiditis secondary multiple evanescent white dot syndrome
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基于Unity3D的Dots寻路算法
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作者 王霞 《信息技术与信息化》 2024年第5期136-139,共4页
自动寻路A*算法的时间复杂度和空间复杂度较高,且对资源消耗较大。通过在Unity3D引擎中结合Dots面向数据的技术堆栈技术,采用ECS+JOBS的工作模式,将过程多线程化,使用JobSystem+Job多线程运行逻辑,对自动寻路的A*算法进行改进,采用修改... 自动寻路A*算法的时间复杂度和空间复杂度较高,且对资源消耗较大。通过在Unity3D引擎中结合Dots面向数据的技术堆栈技术,采用ECS+JOBS的工作模式,将过程多线程化,使用JobSystem+Job多线程运行逻辑,对自动寻路的A*算法进行改进,采用修改地图点密度的方法来降低计算量,性能节省非常明显。为了同时考虑性能问题和寻路表现,再次改进算法,根据寻路对象的个数来动态地改变点与点之间的间隔,并比较两种不同的方案触发寻路,选出最优方案,有效缩短寻路时间,项目可以稳定运行数千个实体角色。 展开更多
关键词 自动寻路 A* 单核多线程 ECS dotS
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Achieving high-efficient photocatalytic persulfate-activated degradation of tetracycline via carbon dots modified MIL-101(Fe)octahedrons 被引量:1
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作者 Hao Yuan Xinhai Sun +2 位作者 Shuai Zhang Weilong Shi Feng Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期298-309,共12页
The synergistic reaction of photocatalysis and advanced oxidation is a valid strategy for the degradation of harmful antibiotic wastewater.Herein,carbon dots(CDs)modified MIL-101(Fe)octahedrons to form CDs/MIL-101(Fe)... The synergistic reaction of photocatalysis and advanced oxidation is a valid strategy for the degradation of harmful antibiotic wastewater.Herein,carbon dots(CDs)modified MIL-101(Fe)octahedrons to form CDs/MIL-101(Fe)composite photocatalyst was synthesized for visible light-driven photocatalytic/persulfate(PS)-activated tetracycline(TC)degradation.The electron spin resonance(ESR)spectra,scavenging experiment and electrochemical analysis were carried out to reveal that the high visible light-driven photocatalytic degradation activity of TC over CDs/MIL-101(Fe)photocatalysts is not only ascribed to the production of free active radicals in the CDs/MIL-101(Fe)/PS system(·OH,·SO_(4-),^(1)O_(2),h^(+)and·O_(2)^(-))but also attributed to the consumption of electrons caused by the PS,which can suppress the recombination of photo-generated carriers as well as strong light scattering and electron trapping effects of CDs.Finally,the possible degradation pathways were proposed by analyzing intermediates via liquid chromatography-mass spectrometry technique.This research presents a rational design conception to construct a CDs/PS-based photocatalysis/advanced oxidation technology with high-efficient degradation activity for the remediation of organic antibiotic pollutant wastewater and for the improvement of carrier transport kinetics of photocatalysts. 展开更多
关键词 Carbon dots MIL-101(Fe) PHOTOCATALYTIC Persulfate activation Tetracycline degradation
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LiCl掺杂PEDOT∶PSS提高蓝光量子点发光二极管的性能
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作者 王艳林 曹松 +2 位作者 余春燕 周利通 翟光美 《液晶与显示》 CAS CSCD 北大核心 2024年第6期771-780,共10页
基于全溶液制备的量子点发光二极管(QLEDs)通常存在电子-空穴注入不平衡的问题,严重地限制了蓝光QLEDs器件性能的提升。本文研究了不同浓度的金属卤化物(Li Cl)掺杂对聚(乙烯二氧噻吩)∶聚苯乙烯磺酸盐(PEDOT∶PSS)薄膜的形貌、导电率... 基于全溶液制备的量子点发光二极管(QLEDs)通常存在电子-空穴注入不平衡的问题,严重地限制了蓝光QLEDs器件性能的提升。本文研究了不同浓度的金属卤化物(Li Cl)掺杂对聚(乙烯二氧噻吩)∶聚苯乙烯磺酸盐(PEDOT∶PSS)薄膜的形貌、导电率、透光性以及所制备QLEDs器件性能的影响规律。实验结果表明,Li Cl的掺杂浓度(质量分数)为2%时蓝光QLED器件性能的提升效果最佳,这主要归因于Li Cl掺杂后的PEDOT∶PSS薄膜导电率和透光性的增强以及器件中空穴注入效率的提高。相较于未掺杂的PEDOT∶PSS基QLED器件,基于Li Cl掺杂的蓝光QLED器件的最大亮度、峰值电流效率、峰值功率效率和峰值外量子效率分别从5 083 cd·m^(-2)、0.91 cd·A^(-1)、0.59 lm·W^(-1)和2.31%提升到7 451 cd·m^(-2)、1.38 cd·A^(-1)、0.89 lm·W^(-1)和3.51%。结果表明,采用Li Cl掺杂PEDOT∶PSS空穴注入层是提高蓝光QLED性能的一种有效策略。 展开更多
关键词 蓝光量子点发光二极管 PEdot∶PSS LiCl掺杂 空穴注入层 空穴注入
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Ultraviolet‑Irradiated All‑Organic Nanocomposites with Polymer Dots for High‑Temperature Capacitive Energy Storage 被引量:1
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作者 Jiale Ding Yao Zhou +5 位作者 Wenhan Xu Fan Yang Danying Zhao Yunhe Zhang Zhenhua Jiang Qing Wang 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期398-406,共9页
Polymer dielectrics capable of operating efficiently at high electric fields and elevated temperatures are urgently demanded by next-generation electronics and electrical power systems.While inorganic fillers have bee... Polymer dielectrics capable of operating efficiently at high electric fields and elevated temperatures are urgently demanded by next-generation electronics and electrical power systems.While inorganic fillers have been extensively utilized to improved high-temperature capacitive performance of dielectric polymers,the presence of thermodynamically incompatible organic and inorganic components may lead to concern about the long-term stability and also complicate film processing.Herein,zero-dimensional polymer dots with high electron affinity are introduced into photoactive allyl-containing poly(aryl ether sulfone)to form the all-organic polymer composites for hightemperature capacitive energy storage.Upon ultraviolet irradiation,the crosslinked polymer composites with polymer dots are efficient in suppressing electrical conduction at high electric fields and elevated temperatures,which significantly reduces the high-field energy loss of the composites at 200℃.Accordingly,the ultraviolet-irradiated composite film exhibits a discharged energy density of 4.2 J cm^(−3)at 200℃.Along with outstanding cyclic stability of capacitive performance at 200℃,this work provides a promising class of dielectric materials for robust high-performance all-organic dielectric nanocomposites. 展开更多
关键词 High-temperature energy storage Polymer dots Ultraviolet irradiation All-organic composite dielectrics
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N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production 被引量:1
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作者 Jingshu Yuan Yao Zhang +2 位作者 Xiaoyan Zhang Junjie Zhang Shen’gen Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期165-178,共14页
Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology r... Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion. 展开更多
关键词 N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis
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Coupling and characterization of a Si/SiGe triple quantum dot array with a microwave resonator
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作者 Shun-Li Jiang Tian-Yi Jiang +8 位作者 Yong-Qiang Xu Rui Wu Tian-Yue Hao Shu-Kun Ye Ran-Ran Cai Bao-Chuan Wang Hai-Ou Li Gang Cao Guo-Ping Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期139-143,共5页
Scaling up spin qubits in silicon-based quantum dots is one of the pivotal challenges in achieving large-scale semiconductor quantum computation.To satisfy the connectivity requirements and reduce the lithographic com... Scaling up spin qubits in silicon-based quantum dots is one of the pivotal challenges in achieving large-scale semiconductor quantum computation.To satisfy the connectivity requirements and reduce the lithographic complexity,utilizing the qubit array structure and the circuit quantum electrodynamics(cQED)architecture together is expected to be a feasible scaling scheme.A triple-quantum dot(TQD)coupled with a superconducting resonator is regarded as a basic cell to demonstrate this extension scheme.In this article,we investigate a system consisting of a silicon TQD and a high-impedance TiN coplanar waveguide(CPW)resonator.The TQD can couple to the resonator via the right double-quantum dot(RDQD),which reaches the strong coupling regime with a charge–photon coupling strength of g0/(2p)=175 MHz.Moreover,we illustrate the high tunability of the TQD through the characterization of stability diagrams,quadruple points(QPs),and the quantum cellular automata(QCA)process.Our results contribute to fostering the exploration of silicon-based qubit integration. 展开更多
关键词 triple-quantum dot strong COUPLING circuit QUANTUM ELECTRODYNAMICS (cQED) scalable siliconbased cQED architectures
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Advantageous properties of halide perovskite quantum dots towards energy-efficient sustainable applications
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作者 Qian Zhao Shuo Wang +9 位作者 Young-Hoon Kim Shekhar Mondal Qingqing Miao Simiao Li Danya Liu Miao Wang Yaxin Zhai Jianbo Gao Abhijit Hazarika Guo-Ran Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第6期949-965,共17页
As lead halide perovskite(LHP)semiconductors have shown tremendous promise in many application fields,and particularly made strong impact in the solar photovoltaic area,low dimensional quantum dot forms of these perov... As lead halide perovskite(LHP)semiconductors have shown tremendous promise in many application fields,and particularly made strong impact in the solar photovoltaic area,low dimensional quantum dot forms of these perovskites are showing the potential to make distinct marks in the fields of electronics,optoelectronics and photonics.The so-called perovskite quantum dots(PQDs)not only possess the most important features of LHP materials,i.e.,the unusual high defect tolerance,but also demonstrate clear quantum size effects,along with exhibiting desirable optoelectronic properties such as near perfect photoluminescent quantum yield,multiple exciton generation and slow hot-carrier cooling.Here,we review the advantageous properties of these nanoscale perovskites and survey the prospects for diverse applications which include lightemitting devices,solar cells,photocatalysts,lasers,detectors and memristors,emphasizing the distinct superiorities as well as the challenges. 展开更多
关键词 Perovskite quantum dot LIGHT-EMITTING Detector Laser Solar cell
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Experimental and computational study of annealed nickel sulfide quantum dots for catalytic and antibacterial activity
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作者 Muhammad Ikram Sawaira Moeen +5 位作者 Ali Haider Anwar Ul-Hamid Haya Alhummiany Hamoud H.Somaily Souraya Goumri-Said Mohammed Benali Kanoun 《Nano Materials Science》 EI CAS CSCD 2024年第3期355-364,共10页
This research investigates the hydrothermal synthesis and annealing duration effects on nickel sulfide(NiS_(2) quantum dots(QDs)for catalytic decolorization of methylene blue(MB)dye and antimicrobial efficacy.QD size ... This research investigates the hydrothermal synthesis and annealing duration effects on nickel sulfide(NiS_(2) quantum dots(QDs)for catalytic decolorization of methylene blue(MB)dye and antimicrobial efficacy.QD size increased with longer annealing,reducing catalytic activity.UV–vis,XRD,TEM,and FTIR analyses probed optical structural,morphological,and vibrational features.XRD confirmed NiS2's anorthic structure,with crystallite size growing from 6.53 to 7.81 nm during extended annealing.UV–Vis exhibited a bathochromic shift,reflecting reduced band gap energy(Eg)in NiS_(2).TEM revealed NiS_(2)QD formation,with agglomerated QD average size increasing from 7.13 to 9.65 nm with prolonged annealing.Pure NiS_(2) showed significant MB decolorization(89.85%)in acidic conditions.Annealed NiS_(2) QDs demonstrated notable antibacterial activity,yielding a 6.15mm inhibition zone against Escherichia coli(E.coli)compared to Ciprofloxacin.First-principles computation supported a robust interaction between MB and NiS_(2),evidenced by obtained adsorption energies.This study highlights the nuanced relationship between annealing duration,structural changes,and functional properties in NiS_(2)QDs,emphasizing their potential applications in catalysis and antibacterial interventions. 展开更多
关键词 NiS_(2) ANTIBACTERIAL quantum dots DYE degradation DFT
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Coupling of BiOCl Ultrathin Nanosheets with Carbon Quantum Dots for Enhanced Photocatalytic Performance
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作者 Pin Song Xiaoyu Fang +14 位作者 Wei Jiang Yuyang Cao Daobin Liu Shiqiang Wei Jun Du Lang Sun Lei Zhao Song Liu Yuzhu Zhou Jun Di Chade Lv Bijun Tang Jiefu Yang Tingting Kong Yujie Xiong 《Transactions of Tianjin University》 EI CAS 2024年第3期211-220,共10页
Over the past few decades,photocatalysis technology has received extensive attention because of its potential to mitigate or solve energy and environmental pollution problems.Designing novel materials with outstanding... Over the past few decades,photocatalysis technology has received extensive attention because of its potential to mitigate or solve energy and environmental pollution problems.Designing novel materials with outstanding photocatalytic activities has become a research hotspot in this field.In this study,we prepared a series of photocatalysts in which BiOCl nanosheets were modified with carbon quantum dots(CQDs)to form CQDs/BiOCl composites by using a simple solvothermal method.The photocatalytic performance of the resulting CQDs/BiOCl composite photocatalysts was assessed by rhodamine B and tetracycline degradation under visible-light irradiation.Compared with bare BiOCl,the photocatalytic activity of the CQDs/BiOCl composites was significantly enhanced,and the 5 wt%CQDs/BiOCl composite exhibited the highest photocatalytic activity with a degradation efficiency of 94.5%after 30 min of irradiation.Moreover,photocatalytic N_(2)reduction performance was significantly improved after introducing CQDs.The 5 wt%CQDs/BiOCl composite displayed the highest photocatalytic N_(2)reduction performance to yield NH_3(346.25μmol/(g h)),which is significantly higher than those of 3 wt%CQDs/BiOCl(256.04μmol/(g h)),7 wt%CQDs/BiOCl(254.07μmol/(g h)),and bare BiOCl(240.19μmol/(g h)).Our systematic characterizations revealed that the key role of CQDs in improving photocatalytic performance is due to their increased light harvesting capacity,remarkable electron transfer ability,and higher photocatalytic activity sites. 展开更多
关键词 Carbon quantum dots BiOCl Rhodamine B TETRACYCLINE PHOTOCATALYSIS
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Effective Activation of Melamine for Synchronous Synthesis of Catalytically Active Nanosheets and Fluorescence-Responsive Quantum Dots
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作者 Jie Xuan Guijian Guan Ming-Yong Han 《Transactions of Tianjin University》 EI CAS 2024年第3期284-296,共13页
Because of the low reactivity of cyclic nitrides,liquid-phase synthesis of carbon nitride introduces challenges despite its favorable potential for energy-efficient preparation and superior applications.In this study,... Because of the low reactivity of cyclic nitrides,liquid-phase synthesis of carbon nitride introduces challenges despite its favorable potential for energy-efficient preparation and superior applications.In this study,we demonstrate a strong interaction between citric acid and melamine through experimental observation and theoretical simulation,which eff ectively activates melamine-condensation activity and produces carbon-rich carbon nitride nanosheets(CCN NSs)during hydrothermal reaction.Under a large specific surface area and increased light absorption,these CCN NSs demonstrate significantly enhanced photocatalytic activity in CO_(2) reduction,increasing the CO production rate by approximately tenfold compared with hexagonal melamine(h-Me).Moreover,the product selectivity of CCN NSs reaches up to 93.5%to generate CO from CO_(2).Furthermore,the annealed CCN NSs exhibit a CO conversion rate of up to 95.30μmol/(g h),which indicates an 18-fold increase compared with traditional carbon nitride.During the CCN NS synthesis,nitrogen-doped carbon quantum dots(NDC QDs)are simultaneously produced and remain suspended in the supernatant after centrifugation.These QDs disperse well in water and exhibit excellent luminescent properties(QY=67.2%),allowing their application in the design of selective and sensitive sensors to detect pollutants such as pesticide 2,4-dichlorophenol with a detection limit of as low as 0.04μmol/L.Notably,the simultaneous synthesis of CCN NSs and NDC QDs provides a cost-eff ective and highly efficient process,yielding products with superior capabilities for catalytic conversion of CO_(2) and pollutant detection,respectively. 展开更多
关键词 Carbon nitride Hydrothermal reaction PHOTOCATALYSIS Carbon dioxide Quantum dots
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Paving continuous heat dissipation pathways for quantum dots in polymer with orangeinspired radially aligned UHMWPE fibers
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作者 Xuan Yang Xinfeng Zhang +3 位作者 Tianxu Zhang Linyi Xiang Bin Xie Xiaobing Luo 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第7期27-38,共12页
Thermal management of nanoscale quantum dots(QDs)in light-emitting devices is a long-lasting challenge.The existing heat transfer reinforcement solutions for QDs-polymer composite mainly rely on thermal-conductive fil... Thermal management of nanoscale quantum dots(QDs)in light-emitting devices is a long-lasting challenge.The existing heat transfer reinforcement solutions for QDs-polymer composite mainly rely on thermal-conductive fillers.However,this strategy failed to deliver the QDs’heat generation across a long distance,and the accumulated heat still causes considerable temperature rise of QDs-polymer composite,which eventually menaces the performance and reliability of lightemitting devices.Inspired by the radially aligned fruit fibers in oranges,we proposed to eliminate this heat dissipation challenge by establishing long-range ordered heat transfer pathways within the QDs-polymer composite.Ultrahigh molecular weight polyethylene fibers(UPEF)were radially aligned throughout the polymer matrix,thus facilitating massive efficient heat dissipation of the QDs.Under a UPEF filling fraction of 24.46 vol%,the in-plane thermal conductivity of QDs-radially aligned UPEF composite(QDs-RAPE)could reach 10.45 W m^(−1) K^(−1),which is the highest value of QDs-polymer composite reported so far.As a proof of concept,the QDs’working temperature can be reduced by 342.5℃ when illuminated by a highly concentrated laser diode(LD)under driving current of 1000 mA,thus improving their optical performance.This work may pave a new way for next generation high-power QDs lighting applications. 展开更多
关键词 quantum dots UHMWPE fibers radial alignment heat dissipation light-emitting devices
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NbN quantum dots anchored hollow carbon nanorods as efficient polysulfide immobilizer and lithium stabilizer for Li-S full batteries
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作者 Fei Ma Zhuo Chen +9 位作者 Katam Srinivas Ziheng Zhang Yu Wu Dawei Liu Hesheng Yu Yue Wang Xinsheng Li Ming-qiang Zhu Qi Wu Yuanfu Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期260-271,I0007,共13页
The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)batteries.To simultaneously address such issues,monodispers... The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)batteries.To simultaneously address such issues,monodispersed Nb N quantum dots anchored on nitrogen-doped hollow carbon nanorods(NbN@NHCR)are elaborately developed as efficient Li PSs immobilizer and Li stabilizer for high-performance Li-S full batteries.Density functional theory(DFT)calculations and experimental characterizations demonstrate that the sulfiphilic and lithiophilic NbN@NHCR hybrid can not only efficiently immobilize the soluble Li PSs and facilitate diffusion-conversion kinetics for alleviating the shuttling effect,but also homogenize the distribution of Li+ions and regulate uniform Li deposition for suppressing Li-dendrite growth.As a result,the assembled Li-S full batteries(NbN@NHCR-S||Nb N@NHCR-Li)deliver excellent long-term cycling stability with a low decay rate of 0.031%per cycle over 1000 cycles at high rate of 2 C.Even at a high S loading of 5.8 mg cm^(-2)and a low electrolyte/sulfur ratio of 5.2μL mg^(-1),a large areal capacity of 6.2 mA h cm^(-2)can be achieved in Li-S pouch cell at 0.1 C.This study provides a new perspective via designing a dual-functional sulfiphilic and lithiophilic hybrid to address serious issues of the shuttle effect of S cathode and dendrite growth of Li anode. 展开更多
关键词 Dual-functional host NbN quantum dots Shuttle effect Dendrite-free Li anode Li-S full batteries
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Majorana tunneling in a one-dimensional wire with non-Hermitian double quantum dots
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作者 牛鹏斌 罗洪刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期686-691,共6页
The combination of non-Hermitian physics and Majorana fermions can give rise to new effects in quantum transport systems. In this work, we investigate the interplay of PT-symmetric complex potentials, Majorana tunneli... The combination of non-Hermitian physics and Majorana fermions can give rise to new effects in quantum transport systems. In this work, we investigate the interplay of PT-symmetric complex potentials, Majorana tunneling and interdot tunneling in a non-Hermitian double quantum dots system. It is found that in the weak-coupling regime the Majorana tunneling has pronounced effects on the transport properties of such a system, manifested as splitting of the single peak into three and a reduced 1/4 peak in the transmission function. In the presence of the PT-symmetric complex potentials and interdot tunneling, the 1/4 central peak is robust against them, while the two side peaks are tuned by them. The interdot tunneling only induces asymmetry, instead of moving the conductance peak, due to the robustness of the Majorana modes. There is an exceptional point induced by the union of Majorana tunneling and interdot tunneling. With increased PT-symmetric complex potentials, the two side peaks will move towards each other. When the exceptional point is passed through, these two side peaks will disappear. In the strong-coupling regime, the Majorana fermion induces a 1/4 conductance dip instead of the three-peak structure. PT-symmetric complex potentials induce two conductance dips pinned at the exceptional point. These effects should be accessible in experiments. 展开更多
关键词 Majorana fermion non-Hermitian quantum dot parity–time symmetry exceptional point
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Threshold-independent method for single-shot readout of spin qubits in semiconductor quantum dots
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作者 胡睿梓 祝圣凯 +9 位作者 张鑫 周圆 倪铭 马荣龙 罗刚 孔真真 王桂磊 曹刚 李海欧 郭国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期274-279,共6页
The single-shot readout data process is essential for the realization of high-fidelity qubits and fault-tolerant quantum algorithms in semiconductor quantum dots. However, the fidelity and visibility of the readout pr... The single-shot readout data process is essential for the realization of high-fidelity qubits and fault-tolerant quantum algorithms in semiconductor quantum dots. However, the fidelity and visibility of the readout process are sensitive to the choice of the thresholds and limited by the experimental hardware. By demonstrating the linear dependence between the measured spin state probabilities and readout visibilities along with dark counts, we describe an alternative threshold-independent method for the single-shot readout of spin qubits in semiconductor quantum dots. We can obtain the extrapolated spin state probabilities of the prepared probabilities of the excited spin state through the threshold-independent method. We then analyze the corresponding errors of the method, finding that errors of the extrapolated probabilities cannot be neglected with no constraints on the readout time and threshold voltage. Therefore, by limiting the readout time and threshold voltage, we ensure the accuracy of the extrapolated probability. We then prove that the efficiency and robustness of this method are 60 times larger than those of the most commonly used method. Moreover, we discuss the influence of the electron temperature on the effective area with a fixed external magnetic field and provide a preliminary demonstration for a single-shot readout of up to 0.7K/1.5T in the future. 展开更多
关键词 quantum computation quantum dot quantum state readout
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Temperature-controlled DCP Fluorescent Probe Based on Hydrogel-immobilized Quantum Dots Composite
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作者 童伊琳 杨坤 +2 位作者 HAN Xuecai YU Kan BAO Jiaqi 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期931-936,共6页
A composite was created by incorporating the quantum dot-enhanced SiO_(2)nanoparticles within this hydrogel.Based on this composite,a temperature-controlled fluorescent probe for DCP was developed.A meticulous examina... A composite was created by incorporating the quantum dot-enhanced SiO_(2)nanoparticles within this hydrogel.Based on this composite,a temperature-controlled fluorescent probe for DCP was developed.A meticulous examination of this probe revealed its attributes and factors affecting its performance.By using temperature modulation,the probe was adept at detecting DCP concentrations ranging between 1.0×10^(-6)and 9.0×10^(-6)mol/L.Such a probe offers remarkable selectivity,repeatability,and robust stability,so that the detection of DCP can be carried out at different temperatures,and a fast,reliable,sensitive and low-cost intelligent detection method is realized. 展开更多
关键词 temperature-controlled fluorescent probe hydrogel-immobilized quantum dots composite DCP
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Small but mighty:Empowering sodium/potassium-ion battery performance with S-doped SnO_(2) quantum dots embedded in N,S codoped carbon fiber network
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作者 Shengnan He Hui Wu +4 位作者 Shuang Li Ke Liu Yaxiong Yang Hongge Pan Xuebin Yu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期186-200,共15页
SnO_(2) has been extensively investigated as an anode material for sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)due to its high Na/K storage capacity,high abundance,and low toxicity.However,the sluggish ... SnO_(2) has been extensively investigated as an anode material for sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)due to its high Na/K storage capacity,high abundance,and low toxicity.However,the sluggish reaction kinetics,low electronic conductivity,and large volume changes during charge and discharge hinder the practical applications of SnO_(2)-based electrodes for SIBs and PIBs.Engineering rational structures with fast charge/ion transfer and robust stability is important to overcoming these challenges.Herein,S-doped SnO_(2)(S-SnO_(2))quantum dots(QDs)(≈3 nm)encapsulated in an N,S codoped carbon fiber networks(S-SnO_(2)-CFN)are rationally fabricated using a sequential freeze-drying,calcination,and S-doping strategy.Experimental analysis and density functional theory calculations reveal that the integration of S-SnO_(2) QDs with N,S codoped carbon fiber network remarkably decreases the adsorption energies of Na/K atoms in the interlayer of SnO_(2)-CFN,and the S doping can increase the conductivity of SnO_(2),thereby enhancing the ion transfer kinetics.The synergistic interaction between S-SnO_(2) QDs and N,S codoped carbon fiber network results in a composite with fast Na+/K+storage and extraordinary long-term cyclability.Specifically,the S-SnO_(2)-CFN delivers high rate capacities of 141.0 mAh g^(−1) at 20 A g^(−1) in SIBs and 102.8 mAh g^(−1) at 10 A g^(−1) in PIBs.Impressively,it delivers ultra-stable sodium storage up to 10,000 cycles at 5 A g^(−1) and potassium storage up to 5000 cycles at 2 A g^(−1).This study provides insights into constructing metal oxide-based carbon fiber network structures for high-performance electrochemical energy storage and conversion devices. 展开更多
关键词 carbon fiber network heteroatom doping potassium-ion battery sodium-ion battery S-SnO_(2)quantum dot
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Embedded high-quality ternary GaAs_(1−x)Sb_(x) quantum dots in GaAs nanowires by molecular-beam epitaxy
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作者 Xiyu Hou Lianjun Wen +6 位作者 Fengyue He Ran Zhuo Lei Liu Hailong Wang Qing Zhong Dong Pan Jianhua Zhao 《Journal of Semiconductors》 EI CAS CSCD 2024年第8期18-24,共7页
Semiconductor quantum dots are promising candidates for preparing high-performance single photon sources.A basic requirement for this application is realizing the controlled growth of high-quality semiconductor quantu... Semiconductor quantum dots are promising candidates for preparing high-performance single photon sources.A basic requirement for this application is realizing the controlled growth of high-quality semiconductor quantum dots.Here,we report the growth of embedded GaAs_(1−x)Sb_(x) quantum dots in GaAs nanowires by molecular-beam epitaxy.It is found that the size of the GaAs_(1−x)Sb_(x) quantum dot can be well-defined by the GaAs nanowire.Energy dispersive spectroscopy analyses show that the antimony content x can be up to 0.36 by tuning the growth temperature.All GaAs_(1−x)Sb_(x) quantum dots exhibit a pure zinc-blende phase.In addition,we have developed a new technology to grow GaAs passivation layers on the sidewalls of the GaAs_(1−x)Sb_(x) quantum dots.Different from the traditional growth process of the passivation layer,GaAs passivation layers can be grown simultaneously with the growth of the embedded GaAs_(1−x)Sb_(x) quantum dots.The spontaneous GaAs passivation layer shows a pure zinc-blende phase due to the strict epitaxial relationship between the quantum dot and the passivation layer.The successful fabrication of embedded high-quality GaAs_(1−x)Sb_(x) quantum dots lays the foundation for the realization of GaAs_(1−x)Sb_(x)-based single photon sources. 展开更多
关键词 semiconductor quantum dot NANOWIRE GaAs_(1−x)Sb_(x) molecular-beam epitaxy
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Highly enhanced UV absorption and light emission of monolayer WS_(2)through hybridization with Ti_(2)N MXene quantum dots and g-C_(3)N_(4)quantum dots
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作者 Anir S.Sharbirin Rebekah E.Kong +5 位作者 Wendy B.Mato Trang Thu Tran Eunji Lee Jolene W.P.Khor Afrizal L.Fadli Jeongyong Kim 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第6期31-39,共9页
Two-dimensional(2D)transition metal dichalcogenides(TMD)are atomically thin semiconductors with promising optoelectronic applications across the visible spectrum.However,their intrinsically weak light absorption and t... Two-dimensional(2D)transition metal dichalcogenides(TMD)are atomically thin semiconductors with promising optoelectronic applications across the visible spectrum.However,their intrinsically weak light absorption and the low photoluminescence quantum yield(PLQY)restrict their performance and potential use,especially in ultraviolet(UV)wavelength light ranges.Quantum dots(QD)derived from 2D materials(2D/QD)provide efficient light absorption and emission of which energy can be tuned for desirable light wavelength.In this study,we greatly enhanced the photon absorption and PLQY of monolayer(1L)tungsten disulfide(WS_(2))in the UV range via hybridization with 2D/QD,particularly titanium nitride MXene QD(Ti_(2)N MQD)and graphitic carbon nitride QD(GCNQD).With the hybridization of MQD or GCNQD,1LWS_(2)showed a maximum PL enhancement by 15 times with 300 nm wavelength excitation,while no noticeable enhancement was observed when the excitation photon energy was less than the bandgap of the QD,indicating that UV absorption by the QD played a crucial role in enhancing the light emission of 1L-WS_(2)in our 0D/2D hybrid system.Our findings present a convenient method for enhancing the photo-response of 1L-WS_(2)to UV light and offer exciting possibilities for harvesting UV energy using 1L-TMD. 展开更多
关键词 monolayer TMD WS_(2) 2D-derived quantum dots UV absorption energy transfer
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