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Two-Dimensional MXene-Based Advanced Sensors for Neuromorphic Computing Intelligent Application
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作者 Lin Lu Bo Sun +2 位作者 Zheng Wang Jialin Meng Tianyu Wang 《Nano-Micro Letters》 2026年第2期664-691,共28页
As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and el... As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and electrochemical characteristics,MXenes have shown great potential in brain-inspired neuromorphic computing electronics,including neuromorphic gas sensors,pressure sensors and photodetectors.This paper provides a forward-looking review of the research progress regarding MXenes in the neuromorphic sensing domain and discussed the critical challenges that need to be resolved.Key bottlenecks such as insufficient long-term stability under environmental exposure,high costs,scalability limitations in large-scale production,and mechanical mismatch in wearable integration hinder their practical deployment.Furthermore,unresolved issues like interfacial compatibility in heterostructures and energy inefficiency in neu-romorphic signal conversion demand urgent attention.The review offers insights into future research directions enhance the fundamental understanding of MXene properties and promote further integration into neuromorphic computing applications through the convergence with various emerging technologies. 展开更多
关键词 two-dimensional MXenes SENSOR Neuromorphic computing Multimodal intelligent system Wearable electronics
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Inhibitory effect of the interlayer of two-dimensional vermiculite on the polysulfide shuttle in lithium-sulfur batteries
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作者 CHEN Xiaoli LUO Zhihong +3 位作者 XIONG Yuzhu WANG Aihua CHEN Xue SHAO Jiaojing 《无机化学学报》 北大核心 2025年第8期1661-1671,共11页
A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface... A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface area of 427 m^(2)·g^(-1)and rich surface active sites,which help restrain polysulfides(LiPSs)through good physi-cal and chemical adsorption,while simultaneously accelerating the nucleation and dissolution kinetics of Li_(2)S,effec-tively suppressing the shuttle effect.The assembled lithium-sulfur batteries(LSBs)employing the PVS-based inter-layer delivered a high initial discharge capacity of 1386 mAh·g^(-1)at 0.1C(167.5 mAh·g^(-1)),long-term cycling stabil-ity,and good rate property. 展开更多
关键词 vermiculite nanosheets two-dimensional materials INTERLAYER shuttle effect lithium-sulfur batteries
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Many-Body Enhancement of Excitonic Electron–Hole Recombination in Two-Dimensional Transition Metal Dichalcogenides
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作者 Li Yao Xiang Jiang +1 位作者 Qijing Zheng Jin Zhao 《Chinese Physics Letters》 2026年第1期134-141,共8页
Electron–hole(e–h)recombination is a fundamental process that governs energy dissipation and device efficiency in semiconductors.In two-dimensional(2D)materials,the formation of tightly bound excitons makes exciton-... Electron–hole(e–h)recombination is a fundamental process that governs energy dissipation and device efficiency in semiconductors.In two-dimensional(2D)materials,the formation of tightly bound excitons makes exciton-mediated e–h recombination the dominant decay pathway.In this work,nonradiative e–h recombination within excitons in monolayer MoS2 is investigated using first-principles simulations that combine nonadiabatic molecular dynamics with𝐺𝑊and real-time Bethe–Salpeter equation(BSE)propagation.A two-step process is identified:rapid intervalley redistribution induced by exchange interaction,followed by slower phonon-assisted recombination facilitated by exciton binding.By selectively removing the screened Coulomb and exchange terms from the BSE Hamiltonian,their respective contributions are disentangled—exchange interaction is found to increase the number of accessible recombination pathways,while binding reduces the excitation energy and enhances nonradiative decay.A reduction in recombination lifetime by over an order of magnitude is observed due to the excitonic many-body effects.These findings provide microscopic insights for understanding and tuning exciton lifetimes in 2D transition-metal dichalcogenides. 展开更多
关键词 energy dissipation tightly bound excitons many body effects excitonic recombination nonadiabatic molecular dynamics e h recombination decay pathwayin monolayer mos
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Analysis of Leakage Effects on Outlet Flow Characteristics of a Two-dimensional Piston Pump
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作者 Yu Huang Hanyu Xu +2 位作者 Wei Shao Chuan Ding Li Liu 《Chinese Journal of Mechanical Engineering》 2025年第3期545-557,共13页
Owing to their rolling friction,two-dimensional piston pumps are highly suitable as power components for electro-hydrostatic actuators(EHAs).These pumps are particularly advantageous for applications requiring high ef... Owing to their rolling friction,two-dimensional piston pumps are highly suitable as power components for electro-hydrostatic actuators(EHAs).These pumps are particularly advantageous for applications requiring high efficiency and reliability.However,the ambiguity surrounding the output flow characteristics of individual two-dimensional pumps poses a significant challenge in achieving precise closed-loop control of the EHA positions.To address this issue,this study established a comprehensive numerical model that included gap leakage to analyze the impact of leakage on the output flow characteristics of a two-dimensional piston pump.The validity of the numerical analysis was indirectly confirmed through meticulous measurements of the leakage and volumetric efficiency,ensuring robust results.The research findings indicated that,at lower pump speeds,leakage significantly affected the output flow rate,leading to potential inefficiencies in the system.Conversely,at higher rotational speeds,the impact of leakage was less pronounced,implying that the influence of leakage on the pump outlet flow must be carefully considered and managed for EHAs to perform position servo control.Additionally,the research demonstrates that two-dimensional motion does not have a unique or additional effect on pump leakage,thus simplifying the design considerations.Finally,the study concluded that maintaining an oil-filled leakage environment is beneficial because it helps reduce the impact of leakage and enhances the overall volumetric efficiency of the pump system. 展开更多
关键词 two-dimensional piston pump LEAKAGE Numerical simulation CLEARANCE
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Two-dimensional vanadium nanosheets as a remarkably effective catalyst for hydrogen storage in MgH_(2) 被引量:24
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作者 Zhi-Yu Lu Hai-Jie Yu +5 位作者 Xiong Lu Meng-Chen Song Fu-Ying Wu Jia-Guang Zheng Zhi-Fei Yuan Liu-Ting Zhang 《Rare Metals》 SCIE EI CAS CSCD 2021年第11期3195-3204,共10页
Magnesium hydride(MgH_(2)),which possesses high hydrogen density of 7.6 wt%,abundant resource and non-toxicity,has captured intense attention as one of the potential hydrogen storage materials.However,the practical ap... Magnesium hydride(MgH_(2)),which possesses high hydrogen density of 7.6 wt%,abundant resource and non-toxicity,has captured intense attention as one of the potential hydrogen storage materials.However,the practical application of Mg/MgH_(2) system is suffering from high thermal stability,sluggish absorption and desorption kinetics.Herein,two-dimensional(2D) vanadium nanosheets(V_(NS)) were successfully prepared via a facile wet chemical ball milling method and proved to be highly effective on improving the hydrogen storage performance of MgH_(2).For instance,the MgH_(2)+7 wt% V_(NS) composite began to release hydrogen at 187.2℃,152 ℃ lower than that of additive-free MgH_(2).At 300℃,6.3 wt% hydrogen was released from the MgH_(2)+7 wt% V_(NS) composite within 10 min.In addition,the fully dehydrogenated sample could absorb hydrogen even at room temperature under hydrogen pressure of 3.2 MPa.X-ray diffractometer(XRD) and transmission electron microscopy(TEM)results confirmed metallic vanadium served as catalytic unit for facilitating the de/rehydrogenation reaction of MgH_(2).This finding presents an example of facile synthesis of two-dimensional(2D) vanadium with excellent catalysis,which may shed light on future design and preparation of highly effective layered catalysts for hydrogen storage and other energy-related areas. 展开更多
关键词 Hydrogen storage Magnesium hydride two-dimensional vanadium nanosheets Catalytic effect
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Phonon Confinement Effect in Two-dimensional Nanocrystallites of Monolayer MoS_2 to Probe Phonon Dispersion Trends Away from Brillouin-Zone Center 被引量:1
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作者 石薇 张昕 +4 位作者 李晓莉 乔晓粉 吴江滨 张俊 谭平恒 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期111-114,共4页
The fundamental momentum conservation requirement q - 0 for the Raman process is relaxed in the nanocrystal- lites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, whi... The fundamental momentum conservation requirement q - 0 for the Raman process is relaxed in the nanocrystal- lites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, which is well-known as the phonon confinement effect in NCs. This usually gives a downshift and asymmetric broadening of the Raman peak in various NCs. Recently, the A1 mode of 1L MoS2 NCs is found to exhibit a blue shift and asymmetric broadening toward the high-frequency side [Chem. Soc. Rev. 44 (2015) 2757 and Phys. Rev. B 91 (2015) 195411]. In this work, we carefully check this issue by studying Raman spectra of lL MoS2 NCs prepared by the ion implantation technique in a wide range of ion-implanted dosage. The same confinement coefficient is used for both E' and A'1 modes in 1L MoS2 NCs since the phonon uncertainty in an NC is mainly determined by its domain size. The asymmetrical broadening near the A'1 and E' modes is attributed to the appearance of defect-activated phonons at the zone edge and the intrinsic asymmetrical broadening of the two modes, where the anisotropy of phonon dispersion curves along Г-K and Г- M is also considered. The photoluminescence spectra confirm the formation of small domain size of 1L MoS2 nanocrystallites in the ion-implanted 1L MoS2. This study provides not only an approach to quickly probe phonon dispersion trends of 2D materials away from Г by the Raman scattering of the corresponding NCs, but also a reference to completely understand the confinement effect of different modes in various nanomaterials. 展开更多
关键词 of is NC as Phonon Confinement effect in two-dimensional Nanocrystallites of Monolayer MoS2 to Probe Phonon Dispersion Trends Away from Brillouin-Zone Center mode in from
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Large-scale two-dimensional nonlinear FE analysis on PGA amplification effect with depth and focusing effect of Fuzhou Basin 被引量:2
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作者 金丹丹 陈国兴 董菲蕃 《Journal of Central South University》 SCIE EI CAS 2014年第7期2894-2903,共10页
Based on the explicit finite element(FE) method and platform of ABAQUS,considering both the inhomogeneity of soils and concave-convex fluctuation of topography,a large-scale refined two-dimensional(2D) FE nonlinear an... Based on the explicit finite element(FE) method and platform of ABAQUS,considering both the inhomogeneity of soils and concave-convex fluctuation of topography,a large-scale refined two-dimensional(2D) FE nonlinear analytical model for Fuzhou Basin was established.The peak ground motion acceleration(PGA) and focusing effect with depth were analyzed.Meanwhile,the results by wave propagation of one-dimensional(1D) layered medium equivalent linearization method were added for contrast.The results show that:1) PGA at different depths are obviously amplified compared to the input ground motion,amplification effect of both funnel-shaped depression and upheaval areas(based on the shape of bedrock surface) present especially remarkable.The 2D results indicate that the PGA displays a non-monotonic decreasing with depth and a greater focusing effect of some particular layers,while the 1D results turn out that the PGA decreases with depth,except that PGA at few particular depth increases abruptly; 2) To the funnel-shaped depression areas,PGA amplification effect above 8 m depth shows relatively larger,to the upheaval areas,PGA amplification effect from 15 m to 25 m depth seems more significant.However,the regularities of the PGA amplification effect could hardly be found in the rest areas; 3) It appears a higher regression rate of PGA amplification coefficient with depth when under a smaller input motion; 4) The frequency spectral characteristic of input motion has noticeable effects on PGA amplification tendency. 展开更多
关键词 seismic effect of basin LARGE-SCALE fluctuation of topography inhomogeneity site focusing effect two-dimensional refined finite element model nonlinear analysis
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Estimation of the effective properties of two-dimensional cellular materials:a review 被引量:4
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作者 Federica Ongaro 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2018年第4期209-230,298,共23页
In a vast number of engineering fields like medicine,aerospace or robotics,materials are required to meet unusual performances that simple homogeneous materials are often not able to fulfil.Consequently,many efforts a... In a vast number of engineering fields like medicine,aerospace or robotics,materials are required to meet unusual performances that simple homogeneous materials are often not able to fulfil.Consequently,many efforts are currently devoted to develop future generations of materials with enhanced properties and unusual functionalities.In many instances,biological systems served as a source of inspiration,as in the case of cellular materials.Commonly observed in nature,cellular materials offer useful combinations of structural properties and low weight,yielding the possibility of coexistence of what used to be antagonistic physical properties within a single material.Due to their peculiar characteristics,they are very promising for engineering applications in a variety of industries including aerospace,automotive,marine and constructions.However,their use is conditional upon the development of appropriate constitutive models for revealing the complex relations between the microstructure's parameters and the macroscopic behavior.From this point of view,a great variety of analytical and numerical techniques have been proposed and exhaustively discussed in recent years.Noteworthy contributions,suggesting different assumptions and techniques are critically presented in this review paper. 展开更多
关键词 CELLULAR materials effectIVE properties COMPUTATIONAL HOMOGENIZATION ANALYTICAL modelling
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Top gate engineering of field-effect transistors based on wafer-scale two-dimensional semiconductors 被引量:1
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作者 Jingyi Ma Xinyu Chen +15 位作者 Yaochen Sheng Ling Tong Xiaojiao Guo Minxing Zhang Chen Luo Lingyi Zong Yin Xia Chuming Sheng Yin Wang Saifei Gou Xinyu Wang Xing Wu Peng Zhou David Wei Zhang Chenjian Wu Wenzhong Bao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第11期243-248,共6页
The investigation of two-dimensional(2D)materials has advanced into practical device applications,such as cascaded logic stages.However,incompatible electrical properties and inappropriate logic levels remain enormous... The investigation of two-dimensional(2D)materials has advanced into practical device applications,such as cascaded logic stages.However,incompatible electrical properties and inappropriate logic levels remain enormous challenges.In this work,a doping-free strategy is investigated by top gated(TG)MoS_(2) field-effect transistors(FETs)using various metal gates(Au,Cu,Ag,and Al).These metals with different work functions provide a convenient tuning knob for controlling threshold voltage(V_(th))for MoS_(2) FETs.For instance,the Al electrode can create an extra electron doping(n-doping)behavior in the MoS_(2) TG-FETs due to a dipole effect at the gate-dielectric interface.In this work,by achieving matched electrical properties for the load transistor and the driver transistor in an inverter circuit,we successfully demonstrate wafer-scale MoS_(2) inverter arrays with an optimized inverter switching threshold voltage(V_(M))of 1.5 V and a DC voltage gain of 27 at a supply voltage(V_(DD))of 3 V.This work offers a novel scheme for the fabrication of fully integrated multistage logic circuits based on wafer-scale MoS_(2) film. 展开更多
关键词 two-dimensional semiconductor MoS_(2) Top gate Field effect transistor Logic inverter
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Effect of particle size and grain composition on two-dimensional infiltration process of weathered crust elution-deposited rare earth ores 被引量:11
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作者 Zhong-qun GUO Yuan-ming LAI +3 位作者 Jie-fang JIN Jian-rong ZHOU Kui ZHAO Zheng SUN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第6期1647-1661,共15页
The two-dimensional infiltration experiment was carried out by means of digital image technology.The evolution process of the wetting body was described.The wetted front distance and the time show a very significant p... The two-dimensional infiltration experiment was carried out by means of digital image technology.The evolution process of the wetting body was described.The wetted front distance and the time show a very significant power function relationship.The horizontal wetted distance is larger than the vertical wetted distance in the initial stage.Then,the vertical distance of the wetted body gradually approaches to the horizontal distance.The infiltration distance decreases as the content of fine particles increases.The wetted front migration rate curve shows a three-stage change law,and it increases with the increase of coarse particle content.The directional velocity ratio is defined.The initial value of horizontal infiltration rate is larger than that of vertical one,and then the vertical infiltration rate is gradually close to the horizontal value.The empirical relationship between the characteristic particle size and the stable infiltration rate is established,which provides a theoretical basis for the prediction of the stable infiltration rate in in-situ leaching. 展开更多
关键词 weathered crust elution-deposited rare earth ores particle size grain composition two-dimensional infiltration wetted front
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Mechanism-based anti-anxiety effects of polysaccharides extracted from Shudihuang (Radix Rehmanniae Preparata) by two-dimensional electrophoresis analysis in rat hippocampus proteins 被引量:19
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作者 Ying Cui Chunlei Rong +5 位作者 Junming Wang Can Cui Li Wang Zhiyi Feng Jing Feng Bing Niu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第4期524-530,共7页
OBJECTIVE: To investigate mechanism-based anti-anxiety effects of Shudihuang (Radix Rehmanniae Preparata) polysaccharides (RRPPs) through two-dimensional electrophoresis (2-DE) analysis with mass spectrometry (MS) of ... OBJECTIVE: To investigate mechanism-based anti-anxiety effects of Shudihuang (Radix Rehmanniae Preparata) polysaccharides (RRPPs) through two-dimensional electrophoresis (2-DE) analysis with mass spectrometry (MS) of hippocampus proteins in rats treated with monosodium L-glutamate (MSG).METHODS: MSG (4 g/kg) or normal saline (NS) was injected subcutaneously into infant male rats on days 2, 4, 6, 8, 10 after birth. MSG-treated rats at 8 weeks old were given NS, diazepam, or RRPPs daily for seven consecutive days by intragastric administration, while NS-treated rats given the same volume of NS. Elevated plus maze (EPM) and light/ dark transition (LDT) tests were used to observe anti-anxiety effects of RRPPs at 1 h after the last administration. After EPM and LDT tests, hippocampus tissues were excised on ice rapidly from the brains of rats. Thereafter, 2-DE and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) were used for detecting differential proteins in hippocampus of rats so as to explore the potential mechanisms. RESULTS: RRPPs (200, 400 mg/kg) could significantly inhibit MSG-induced decrease of time and entries percentages in open zones in EPM test and numbers of light-dark transition in LDT test. Further analysis of 2-DE and MALDI-TOF/MS indicated that β-synuclein, protein DJ-1, peroxiredoxin-2, peroxiredoxin-6, dimethylarginine dimethylaminohydrolase 1 (DDAH-1) and iron-sulfur proteins were all found to be down-regulated significantly in MSG-treated rats, while such down-regulation was significantly inhibited after treatment with RRPPs. CONCLUSION: RRPPs showed anti-anxiety effects and potential mechanisms might be related to inhibiting MSG-induced down-regulation of β-synuclein, DJ-1, peroxiredoxin-2, peroxiredoxin-6, DDAH-1 and iron-sulfur proteins in hippocampus of rats. 展开更多
关键词 ELECTROPHORESIS GEL two-dimensional Beta-synuclein DJ-1 protein Peroxiredoxins Dimethylargininase Iron-sulfur proteins Anti-anxiety agents
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Wearable Biodevices Based on Two-Dimensional Materials:From Flexible Sensors to Smart Integrated Systems 被引量:1
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作者 Yingzhi Sun Weiyi He +3 位作者 Can Jiang Jing Li Jianli Liu Mingjie Liu 《Nano-Micro Letters》 2025年第5期207-255,共49页
The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an over... The proliferation of wearable biodevices has boosted the development of soft,innovative,and multifunctional materials for human health monitoring.The integration of wearable sensors with intelligent systems is an overwhelming tendency,providing powerful tools for remote health monitoring and personal health management.Among many candidates,two-dimensional(2D)materials stand out due to several exotic mechanical,electrical,optical,and chemical properties that can be efficiently integrated into atomic-thin films.While previous reviews on 2D materials for biodevices primarily focus on conventional configurations and materials like graphene,the rapid development of new 2D materials with exotic properties has opened up novel applications,particularly in smart interaction and integrated functionalities.This review aims to consolidate recent progress,highlight the unique advantages of 2D materials,and guide future research by discussing existing challenges and opportunities in applying 2D materials for smart wearable biodevices.We begin with an in-depth analysis of the advantages,sensing mechanisms,and potential applications of 2D materials in wearable biodevice fabrication.Following this,we systematically discuss state-of-the-art biodevices based on 2D materials for monitoring various physiological signals within the human body.Special attention is given to showcasing the integration of multi-functionality in 2D smart devices,mainly including self-power supply,integrated diagnosis/treatment,and human–machine interaction.Finally,the review concludes with a concise summary of existing challenges and prospective solutions concerning the utilization of2D materials for advanced biodevices. 展开更多
关键词 two-dimensional material Wearable biodevice Flexible sensor Smart integrated system Healthcare
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Field-effect transistors based on two-dimensional materials for logic applications 被引量:2
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作者 王欣然 施毅 张荣 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期147-161,共15页
Field-effect transistors (FETs) for logic applications, graphene and MoS2, are discussed. These materials have based on two representative two-dimensional (2D) materials, drastically different properties and requi... Field-effect transistors (FETs) for logic applications, graphene and MoS2, are discussed. These materials have based on two representative two-dimensional (2D) materials, drastically different properties and require different consider- ations. The unique band structure of graphene necessitates engineering of the Dirac point, including the opening of the bandgap, the doping and the interface, before the graphene can be used in logic applications. On the other hand, MoS2 is a semiconductor, and its electron transport depends heavily on the surface properties, the number of layers, and the carrier density. Finally, we discuss the prospects for the future developments in 2D material transistors. 展开更多
关键词 graphene MOS2 two-dimensional (2D) materials field-effect transistors
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Thermal resistance matrix representation of thermal effects and thermal design of microwave power HBTs with two-dimensional array layout 被引量:2
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作者 Rui Chen Dong-Yue Jin +5 位作者 Wan-Rong Zhang Li-Fan Wang Bin Guo Hu Chen Ling-Han Yin Xiao-Xue Jia 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第9期373-380,共8页
Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resist... Based on the thermal network of the two-dimensional heterojunction bipolar transistors(HBTs) array, the thermal resistance matrix is presented, including the self-heating thermal resistance and thermal coupling resistance to describe the self-heating and thermal coupling effects, respectively.For HBT cells along the emitter length direction, the thermal coupling resistance is far smaller than the self-heating thermal resistance, and the peak junction temperature is mainly determined by the self-heating thermal resistance.However, the thermal coupling resistance is in the same order with the self-heating thermal resistance for HBT cells along the emitter width direction.Furthermore, the dependence of the thermal resistance matrix on cell spacing along the emitter length direction and cell spacing along the emitter width direction is also investigated, respectively.It is shown that the moderate increase of cell spacings along the emitter length direction and the emitter width direction could effectively lower the self-heating thermal resistance and thermal coupling resistance,and hence the peak junction temperature is decreased, which sheds light on adopting a two-dimensional non-uniform cell spacing layout to improve the uneven temperature distribution.By taking a 2 × 6 HBTs array for example, a twodimensional non-uniform cell spacing layout is designed, which can effectively lower the peak junction temperature and reduce the non-uniformity of the dissipated power.For the HBTs array with optimized layout, the high power-handling capability and thermal dissipation capability are kept when the bias voltage increases. 展开更多
关键词 HETEROJUNCTION BIPOLAR transistors(HBTs) array THERMAL effects THERMAL resistance MATRIX THERMAL design
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Finite-Time Expected Present Value of Operating Costs until Ruin in a Two-Dimensional Risk Model with Periodic Observation
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作者 TENG Ye XIE Jiayi ZHANG Zhimin 《应用概率统计》 北大核心 2025年第5期748-765,共18页
This paper investigates ruin,capital injection,and dividends for a two-dimensional risk model.The model posits that surplus levels of insurance companies are governed by a perturbed composite Poisson risk model.This m... This paper investigates ruin,capital injection,and dividends for a two-dimensional risk model.The model posits that surplus levels of insurance companies are governed by a perturbed composite Poisson risk model.This model introduces a dependence between the two surplus levels,present in both the associated perturbations and the claims resulting from common shocks.Critical levels of capital injection and dividends are established for each of the two risks.The surplus levels are observed discretely at fixed intervals,guiding decisions on capital injection,dividends,and ruin at these junctures.This study employs a two-dimensional Fourier cosine series expansion method to approximate the finite time expected discounted operating cost until ruin.The ensuing approximation error is also quantified.The validity and accuracy of the method are corroborated through numerical examples.Furthermore,the research delves into the optimal capital allocation problem. 展开更多
关键词 two-dimensional risk model Fourier cosine expansion capital injection DIVIDEND
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Two-dimensional numerical research on effects of titanium target bombarded by TEMPⅡ accelerator 被引量:1
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作者 吴迪 宫野 +3 位作者 刘金远 王晓钢 刘悦 马腾才 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第11期2682-2687,共6页
Two-dimensional numerical research has been carried out on the ablation effects of titanium target irradiated by intense pulsed ion beam (IPIB) generated by TEMP Ⅱ accelerator. Temporal and spatial evolution of the... Two-dimensional numerical research has been carried out on the ablation effects of titanium target irradiated by intense pulsed ion beam (IPIB) generated by TEMP Ⅱ accelerator. Temporal and spatial evolution of the ablation process of the target during a pulse time has been simulated. We have come to the conclusion that the melting and evaporating process begin from the surface and the target is ablated layer by layer when the target is irradiated by the IPIB. Meanwhile, we also obtained the result that the average ablation velocity in target central region is about 10 m/s, which is far less than the ejection velocity of the plume plasma formed by irradiation. Different effects have been compared to the different ratio of the ions and different energy density of IPIB while the target is irradiated by pulsed beams. 展开更多
关键词 intense pulsed ion beam two-dimensional numerical model ablation process TITANIUM
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Unique high-energy excitons in two-dimensional transition metal dichalcogenides
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作者 Yongsheng Gao Yuanzheng Li +5 位作者 Weizhen Liu Chuxin Yan Qingbin Wang Wei Xin Haiyang Xu Yichun Liu 《Chinese Physics B》 2025年第9期445-463,共19页
Two-dimensional(2D)transition metal dichalcogenides(TMDs),endowed with exceptional light-matter interaction strength,have become a pivotal platform in advanced optoelectronics,enabling atomically precise control of ex... Two-dimensional(2D)transition metal dichalcogenides(TMDs),endowed with exceptional light-matter interaction strength,have become a pivotal platform in advanced optoelectronics,enabling atomically precise control of excitonic phenomena and offering transformative potential for engineering next-generation optoelectronic devices.In contrast to the narrowband absorption characteristics of conventional band-edge excitons,which are limited by the bandgap energy,highenergy excitons not only demonstrate broad momentum matching capability in the ultraviolet regime due to band nesting effects,but also exhibit distinct absorption peak signatures owing to robust excitonic stabilization under 2D confinement.These unique photophysical properties have established such systems as a prominent research frontier in contemporary exciton physics.This review primarily outlines the distinctive physical characteristics of high-energy excitons in TMDs from the perspectives of band structure,excitonic characteristics,and optical properties.Subsequently,we systematically delineate cutting-edge developments in TMD-based photonic devices exploiting high-energy excitonic band-nesting phenomena,with dedicated emphasis on the strategic engineering of nanoscale heterostructures for tailored optoelectronic functionality.Finally,the discussion concludes with an examination of the challenges associated with the design of high-energy exciton devices and their potential future applications. 展开更多
关键词 two-dimensional materials transition metal dichalcogenides high-energy excitons band nesting effect optoelectronic applications
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Magnus Hall Effect in Two-Dimensional Materials
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作者 Rui-Chun Xiao Zibo Wang +2 位作者 Zhi-Qiang Zhang Junwei Liu Hua Jiang 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第5期72-77,共6页
The Magnus Hall effect(MHE) is a new type of linear-response Hall effect, recently proposed to appear in two-dimensional(2D) nonmagnetic systems at zero magnetic field in the ballistic limit. The MHE arises from a sel... The Magnus Hall effect(MHE) is a new type of linear-response Hall effect, recently proposed to appear in two-dimensional(2D) nonmagnetic systems at zero magnetic field in the ballistic limit. The MHE arises from a self-rotating Bloch electron moving under a gradient-electrostatic potential, analogous to the Magnus effect in the macrocosm. Unfortunately, the MHE is usually accompanied by a trivial transverse signal, which hinders its experimental observation. We systematically investigate the material realization and experimental measurement of the MHE, based on symmetry analysis and first-principles calculations. It is found that both the out-ofplane mirror and in-plane two-fold symmetries can neutralize the trivial transverse signal to generate clean MHE signals. We choose two representative 2D materials, monolayer MoS_(2), and bilayer WTe_(2), to study the quantitative dependency of MHE signals on the direction of the electric field. The results are qualitatively consistent with the symmetry analysis, and suggest that an observable MHE signal requires giant Berry curvatures. Our results provide detailed guidance for the future experimental exploration of MHE. 展开更多
关键词 MHE Magnus Hall effect in two-dimensional Materials
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Discovery of Two-Dimensional Quantum Spin Hall Effect in Triangular Transition-Metal Carbides
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作者 Shou-juan Zhang Wei-xiao Ji +4 位作者 Chang-wen Zhang Shu-feng Zhang Ping Li Sheng-shi Li Shi-shen Yan 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第8期83-87,共5页
Though the quantum spin Hall effect(QSHE) in two-dimensional(2 D) crystals has been widely explored, the experimental realization of quantum transport properties is only limited to HgTe/CdTe or InAs/GaSb quantum w... Though the quantum spin Hall effect(QSHE) in two-dimensional(2 D) crystals has been widely explored, the experimental realization of quantum transport properties is only limited to HgTe/CdTe or InAs/GaSb quantum wells. Here we employ a tight-binding model on the basis of d(z^2), d(xy), and d(x^2-y^2) orbitals to propose QSHE in the triangular lattice, which are driven by a crossing of electronic bands at the Γ point. Remarkably, 2 D oxidized Mxenes W2 M2 C3 are ideal materials with nontrivial gap of 0.12 eV, facilitating room-temperature observations in experiments. We also find that the nontrivially topological properties of these materials are sensitive to the cooperative effect of the electron correlation and spin-orbit coupling. Due to the feasible exfoliation from its 3 D MAX phase, our work paves a new direction towards realizing QSHE with low dissipation. 展开更多
关键词 SOC Discovery of two-dimensional Quantum Spin Hall effect in Triangular Transition-Metal Carbides
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MXenes-based separators with nanoconfined two-dimensional channels for high-performance lithium-sulfur battery
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作者 Yi-Hui Zhao Shuai Li +6 位作者 Yu-Lu Huo Zhen Li Lan-Lan Hou Yong-Qiang Wen Xiao-Xian Zhao Jian-Jun Song Jing-Chong Liu 《Rare Metals》 2025年第5期2921-2944,共24页
Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major ch... Lithium-sulfur(Li-S)batteries with high energy density and capacity have garnered significant research attention among various energy storage devices.However,the shuttle effect of polysulfides(LiPSs)remains a major challenge for their practical application.The design of battery separators has become a key aspect in addressing the challenge.MXenes,a promising two-dimensional(2D)material,offer exceptional conductivity,large surface area,high mechanical strength,and active sites for surface reactions.When assembled into layered films,MXenes form highly tunable two-dimensional channels ranging from a few angstroms to over 1 nm.These nanoconfined channels are instrumental in facilitating lithium-ion transport while effectively impeding the shuttle effect of LiPSs,which are essential for improving the specific capacity and cyclic stability of Li-S batteries.Substantial progress has been made in developing MXenes-based separators for Li-S batteries,yet there remains a research gap in summarizing advancements from the perspective of interlayer engineering.This entails maintaining the 2D nanochannels of layered MXenes-based separators while modulating the physicochemical environment within the MXenes interlayers through targeted modifications.This review highlights advancements in in situ modification of MXenes and their integration with 0D,1D,and 2D materials to construct laminated nanocomposite separators for Li-S batteries.The future development directions of MXenes-based materials in Li-S energy storage devices are also outlined,to drive further advancements in MXenes for Li-S battery separators. 展开更多
关键词 Lithium-sulfur battery MXenes SEPARATOR two-dimensional materials two-dimensional nanochannels
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