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一种基于Direct Show技术的MPEG-2 TS流的实时传输系统
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作者 赵桦 罗晓富 +2 位作者 林白 程军 李欧 《中国有线电视》 2005年第5期458-460,共3页
运用实例详细阐述了一个简单的MPEG-2TS流实时传输系统的解决方案,着重于几个关键的技术:DirectShow技术、Socket技术、双缓冲技术,以及源过滤器的设计、过滤图的创建、过滤器的Read方法实现。
关键词 direct show SOCKET 过滤器 MPEG-2 TS流 双缓冲队列技术
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基于Direct Show的监控软件的设计与实现
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作者 戚华春 黄德才 《中国有线电视》 2005年第3期313-316,共4页
首先分析监控系统的现状,指出目前存在的两个问题:各个厂家提供的视频捕获卡的系统开发包不一致,导致软件开发效率不高;监控服务器之间的管理紊乱。针对以上两个问题,给出基于DirectShow的监控软件的设计方案以及解决方法。
关键词 监控系统 directshow 过滤器
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应用Direct Show进行视频捕捉的开发
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作者 凌旭东 《黑龙江科技信息》 2009年第36期125-125,共1页
使用摄像头或数码相机,通过视频采集卡,使用DirectShow技术将镜头内容捕捉模拟视频信息转化为数字视频信息到计算机中,并转化为ASF视频文件。
关键词 direct show VIDEO CAPTURE WDM
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基于Direct Show的视频叠加
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作者 李霏 王勇 《技术与市场》 2007年第1期39-40,共2页
本文介绍了视频采集和流媒体回放,着重研究了基于Direct Show架构的多路视频的混合叠加,并给出了使用VMR的解决方案。
关键词 COM组件技术 direct show VMR
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基于Microsoft Direct Show的多媒体应用程序开发
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作者 张俊 《电子技术与软件工程》 2016年第10期97-97,共1页
Microsoft Direct Show是微软Windows平台中的SDK的重要组成部分,是一款新推出的基于Direct X和COM技术的多媒体应用程序开发包,可以很方便地开发出具备高性能和高质量要求的多媒体应用程序,是未来多媒体应用程序的开发方向。本文将从Di... Microsoft Direct Show是微软Windows平台中的SDK的重要组成部分,是一款新推出的基于Direct X和COM技术的多媒体应用程序开发包,可以很方便地开发出具备高性能和高质量要求的多媒体应用程序,是未来多媒体应用程序的开发方向。本文将从Direct Show的基本结构出发,分析和探讨Microsoft Direct Show的平台程序使用方法。 展开更多
关键词 direct show 多媒体应用 程序开发
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S-scheme unidirectional transmission of CdS-CuO heterojunction benefits for superior photocatalytic hydrogen evolution efficiency
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作者 ZHAO Haiting YAN Zheng +2 位作者 LIU Yang JIANG Longde LUAN Jingde 《燃料化学学报(中英文)》 北大核心 2026年第1期1-14,共14页
The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ... The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion. 展开更多
关键词 photocatalytic hydrogen evolution CdS-CuO S-scheme heterojunction electron directional transmission interfacial electric field DFT calculation
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Effect of Cyclic Heat Treatment on Fatigue Crack Growth Rate of Ti-6Al-4V-1Mo Alloy Prepared by Laser Directed Energy Deposition
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作者 Xue Lipan Zhang Fengying +6 位作者 Deng Yulin Ye Zimeng Zhao Kexin Yu Zerong Wu Wenlu Su Wei Yang Renjie 《稀有金属材料与工程》 北大核心 2026年第2期292-301,共10页
The fatigue crack growth rate of a novel Ti-6Al-4V-1Mo titanium alloy,which is developed for laser directed energy deposition technique,was investigated before and after cyclic heat treatment(CHT).Changes in microstru... The fatigue crack growth rate of a novel Ti-6Al-4V-1Mo titanium alloy,which is developed for laser directed energy deposition technique,was investigated before and after cyclic heat treatment(CHT).Changes in microstructure,fracture surfaces,and crack growth paths were analyzed before and after CHT.Results indicate that in the stable crack growth region,the growth rates for the as-deposited and cyclic heat-treated specimens follow the relationships da/dN=1.8651×10^(−8)(ΔK)^(3.2271)and da/dN=1.4112×10^(−8)(ΔK)^(3.1125),respectively.Compared with that at the as-deposited state,the microstructure after CHT is transformed from a uniform basket-weave microstructure to a dual-phase microstructure consisting of near-sphericalαandβ-transformed matrix phases.The cyclic process also disrupts the continuity of the grain boundaryα(αGB)at the primaryβ-phase grain boundary.The coarsening of primaryαand the disruption ofαGB continuity are the primary factors to release stress concentration and promote crack deflection,thereby decreasing the fatigue crack growth rate.Additionally,the increased occurrence of crack branching,secondary cracking,and crack bridging in cyclic heat-treated specimens further reduces the crack driving force and slows the fatigue crack growth rate. 展开更多
关键词 Ti-6Al-4V-1Mo alloy CHT fatigue crack growth rate laser directed energy deposition
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Directional Three‑Dimensional Macroporous Carbon Foams Decorated with WC_(1−x)Nanoparticles Derived from Salting‑Out Protein Assemblies for Highly Effective Electromagnetic Absorption
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作者 Yongzheng Chen Lixue Gai +5 位作者 Bo Hu Yan Wang Yanyi Chen Xijiang Han Ping Xu Yunchen Du 《Nano-Micro Letters》 2026年第3期1-21,共21页
Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usu... Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usually involves complex procedures and extremely depends on unidirectional freezing technique.Herein,we propose a groundbreaking approach that leverages the assemblies of salting-out protein induced by ammonium metatungstate(AM)as the precursor,and then acquire directional three-dimensional carbon-based foams through simple pyrolysis.The electrostatic interaction between AM and protein ensures well dispersion of WC_(1−x)nanoparticles on carbon frameworks.The content of WC_(1−x)nanoparticles can be rationally regulated by AM dosage,and it also affects the electromagnetic(EM)properties of final carbon-based foams.The optimized foam exhibits exceptional EM absorption performance,achieving a remarkable minimum reflection loss of−72.0 dB and an effective absorption bandwidth of 6.3 GHz when EM wave propagates parallel to the directional pores.Such performance benefits from the synergistic effects of macroporous architecture and compositional design.Although there is a directional dependence of EM absorption,radar stealth simulation demonstrates that these foams can still promise considerable reduction in radar cross section with the change of incident angle.Moreover,COMSOL simulation further identifies their good performance in preventing EM interference among different electronic components. 展开更多
关键词 3D macroporous carbon-based foams directional pore channels Salting-out protein assemblies EM wave absorption directional dependence
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Studies of directed flow with event plane method in the HIRFL-CSR external-target experiment
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作者 Wan-Long Wu Xiong-Hong He +3 位作者 Yan-Yu Ren Di-Yu Shen Shu-Su Shi Xu Sun 《Nuclear Science and Techniques》 2026年第4期19-27,共9页
The Cooling-Storage-Ring External-target Experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL)is designed to study the properties of nuclear matter created in heavy-ion collisions at beam energies from a... The Cooling-Storage-Ring External-target Experiment(CEE)at the Heavy Ion Research Facility in Lanzhou(HIRFL)is designed to study the properties of nuclear matter created in heavy-ion collisions at beam energies from a few hundred MeV/u up to 1 GeV/u.It aims to facilitate research on the quantum chromodynamics(QCD)phase structure in the high-baryondensity region.Collective flow is a fundamental observable in heavy-ion collision experiments,providing information on the bulk properties of the produced matter.Although the standard event plane method has been widely used to measure collective flow,it is still important to validate and optimize this method for the CEE spectrometer.In this paper,we study the experimental procedures for measuring directed flow in^(238)U+^(238)U collisions at 500 MeV/u,using event planes reconstructed by Multi-Wire Drift Chamber and Zero Degree Calorimeter,respectively.Jet AA Microscopic(JAM)transport generator is used to generate events,and the detector response is simulated by the CEE Fast Simulation(CFS)package.Finally,the optimal kinematic region for proton directed flow measurements is discussed for the future CEE experiment. 展开更多
关键词 Heavy-ion collisions CEE directed flow Event plane
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Advanced direct recycling enables upcycling of spent lithium-ion batteries
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作者 Wei Liu Linfeng Peng +2 位作者 Ziqi Zeng Shijie Cheng Jia Xie 《Science China Chemistry》 2026年第2期619-639,共21页
The rapid expansion of lithium-ion batteries in electric vehicles and grid-scale energy storage intensify the demand for sustainable recycling strategies.Traditional metallurgical recycling methods face significant ch... The rapid expansion of lithium-ion batteries in electric vehicles and grid-scale energy storage intensify the demand for sustainable recycling strategies.Traditional metallurgical recycling methods face significant challenges,including high energy consumption,environmental pollution,and inefficient critical metals recovery.In contrast,advanced direct recycling can selectively extract valuable metals while preserving cathode structure,achieving over 99%lithium recovery from lithium iron phosphate.Moreover,by directly repairing defects and crystal structures of spent materials,their electrochemical performance can be effectively restored.Due to significantly reduced energy and reagent inputs,direct recycling cuts processing costs by over 20% and reduces waste emissions by at least 40% compared to conventional methods,making it a promising low-carbon alternative.This review systematically integrates the recent advances in direct recycling of spent batteries as well as the limitations and challenges of existing technologies,and proposes future research pathways to promote resource recycling and sustainable development. 展开更多
关键词 lithium-ion battery spent cathode direct recycling metal recovery SUSTAINABILITY
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Interventional Room Nursing for Patients with Ischemic Stroke Treated with Tirofiban Combined with Direct Thrombectomy
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作者 Yayun Xiong 《Journal of Clinical and Nursing Research》 2026年第1期214-220,共7页
Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic s... Objective:To explore the interventional room nursing and its application effects in patients with ischemic stroke treated with tirofiban combined with direct thrombectomy.Methods:A total of 61 patients with ischemic stroke admitted to our hospital from June 2024 to June 2025 were selected and divided into two groups using the red and blue ball method:the control group(n=30,receiving routine interventional room nursing)and the observation group(n=31,receiving additional tirofiban medication-specific nursing+individualized interventional nursing on the basis of routine nursing).The cerebral hemodynamic indicators,adverse reactions,effectiveness of complication nursing,and nursing satisfaction were compared between the two groups.Results:After 7 days of treatment,the observation group had lower cerebrovascular peripheral resistance and higher mean blood flow velocity and mean blood flow volume compared to the control group(all p<0.05).The observation group had a higher effectiveness rate of complication nursing than the control group,with a statistically significant difference(p<0.05).The nursing satisfaction in the observation group(96.77%)was higher than that in the control group(80.00%),with a statistically significant difference(χ^(2)=4.223,p=0.040<0.05).Conclusion:Tirofiban combined with direct thrombectomy can significantly improve cerebral hemodynamics,enhance the effectiveness of complication nursing,and increase patient satisfaction in patients with ischemic stroke. 展开更多
关键词 Tirofiban direct thrombectomy Ischemic stroke Interventional room nursing Nursing coordination
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear... BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level. 展开更多
关键词 Patterns of utilization Antipsychotic drugs direct medical cost SCHIZOPHRENIA DRUGS
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Femtosecond Laser Direct Writing of Biopolymeric Nanocomposite for Biocompatible 3D Features
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作者 Feng Jin Xian-Zi Dong +1 位作者 Jie Liu Mei-Ling Zheng 《Chinese Journal of Polymer Science》 2026年第2期465-473,I0014,共10页
Biopolymeric nanocomposites have attracted considerable attention because of their biocompatibility,biodegradability,and unique physicochemical properties.It is essential to manufacture three-dimensional(3D)biocompati... Biopolymeric nanocomposites have attracted considerable attention because of their biocompatibility,biodegradability,and unique physicochemical properties.It is essential to manufacture three-dimensional(3D)biocompatible micro/nanostructures using biopolymeric nanocomposites.Herein,we demonstrate the high-fidelity fabrication of biocompatible 3D features with sub-50 nm resolution using femtosecond laser direct writing(FsLDW)of a biopolymeric nanocomposite composed of egg white and sulfonated graphene(S-graphene).The biopolymer nanocomposite acts as a negative photoresist suitable for water-based lithography.The introduction of S-graphene not only dramatically lowered the laser power threshold but also significantly modulated the morphology of the 3D features constructed by FsLDW.Microstructures with porous,rough,or smooth morphologies were obtained by optimizing the S-graphene concentration and laser scanning speed.The fabricated egg-white/S-graphene microstructures exhibited biocompatibility and environmental degradability.Egg white/S-graphene was also employed to fabricate diffractive gratings with superior optical quality.This study provides a promising method to manufacture biocompatible 3D features with controllable morphology,which has potential applications in biological and photonic fields. 展开更多
关键词 Femtosecond laser direct writing Biopolymeric nanocomposite Egg white Sulfonated graphene PHOTORESIST
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Multi-frequency non-reciprocal optical directional amplifier realized with non-Hermitian resonator arrays
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作者 Jin-Xiang Xue Chuan-Xun Du +2 位作者 Cheng-Chao Liu Liu Yang Yong-Long Wang 《Chinese Physics B》 2026年第2期423-432,共10页
For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add c... For a multi-frequency non-reciprocal optical device,we first realize multi-frequency optical non-reciprocal transmission using a non-Hermitian multi-mode resonator array.Practically,multi-frequency operation can add channels to the non-reciprocal optical device and the non-reciprocity can route optical signals and prevent the reverse flow of noise.Using the Scully–Lamb model and gain saturation effect,we accomplish dual-frequency non-reciprocal transmission by introducing nonlinearity into a linear array of four-mode resonators.The accomplishment is directly demonstrated by the non-reciprocal transmission phenomena present in the non-divergent peaks.For example,a directional cyclic amplifier is constructed with non-reciprocal units.Regarding potential applications,non-reciprocal optical systems can be employed in dual-frequency control,parallel information processing,photonic integrated circuits,optical devices and so on. 展开更多
关键词 non-Hermitian systems PT-SYMMETRY multi-frequency of non-reciprocity optical directional amplifier
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Does transcranial direct current stimulation enhance the hypoalgesic effect of exercise?
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作者 Aidan Lewis Ben Rattray +1 位作者 Constantino Toufexis Andrew Flood 《Sports Medicine and Health Science》 2026年第1期102-109,共8页
Exercise produces a decrease in pain sensitivity via an effect called exercise-induced hypoalgesia(EIH).Transcranial direct current stimulation(tDCS),acting on similar analgesic mechanisms as EIH,represents a potentia... Exercise produces a decrease in pain sensitivity via an effect called exercise-induced hypoalgesia(EIH).Transcranial direct current stimulation(tDCS),acting on similar analgesic mechanisms as EIH,represents a potential complementary intervention that may amplify the effects of exercise on pain.This study aimed to explore if anodal tDCS could enhance the effect of exercise on pain compared to exercise alone.A total of 35 healthy participants aged 19–37 years completed a familiarisation session followed by two separate sessions where active and sham tDCS was applied in a randomised cross-over design.The familiarisation session involved familiarisation to the pain assessment and exercise tasks,while the subsequent tDCS sessions involved pain sensitivity assessment,exercise and either anodal tDCS or sham tDCS.tDCS doses were applied at 2 mA over the primary motor cortex for 10 min,with the reference electrode placed over the contralateral supraorbital area.The exercise task involved a sustained isometric grip strength contraction at 35%of maximal voluntary contraction(MVC)until volitional exhaustion.Pain sensitivity was evaluated as pressure pain threshold before tDCS,after tDCS,and after exercise.Across both tDCS conditions,pain threshold was higher after exercise when compared to pre-and post-tDCS measurement.This increase in pain threshold did not differ between active and sham tDCS conditions.Our findings suggest that the hypoalgesic effects of active anodal tDCS over the motor cortex prior to exercise are no greater than the effects of sham tDCS prior to exercise. 展开更多
关键词 Transcranial direct current stimulation Grip strength Pain sensitivity Time to exhaustion Pain pressure threshold TDCS
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Energy Efficient Covert Communication in a Direct Uplink Satellite-Ground Communication Scenario
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作者 Fu Shu Zeng Wen +1 位作者 Yin Liuguo Zhao Lian 《China Communications》 2026年第1期166-174,共9页
Efficient energy utilization in covert communication sustains covertness while assuring communication quality and efficiency.This paper investigates covert communication energy efficiency(EE)in direct uplink satellite... Efficient energy utilization in covert communication sustains covertness while assuring communication quality and efficiency.This paper investigates covert communication energy efficiency(EE)in direct uplink satellite-ground communications,focusing on enhancing system EE via optimized transmit beamforming and satellite orbit altitude selection.This paper first establishes an optimization problem to maximize system EE in a direct uplink satelliteground covert communication scenario.To solve this non-convex optimization problem,it is decomposed into two subproblems and solved using the successive convex approximation(SCA)method.Based on the above methods,this paper proposes an overall iterative optimization algorithm.Simulation results demonstrate that the proposed algorithm surpasses the conventional baseline algorithms in terms of system EE.Furthermore,they elucidate the correlation between the amount of information received by the receiver and the variations in the satellite’s orbital altitude. 展开更多
关键词 covert communication direct uplink satellite-ground communication energy efficiency
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Facile fabrication of twisted MoS_(2) bilayers by direct bonding
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作者 Yu-Tong Chen Jie-Ying Liu +6 位作者 Lan-Ying Zhou Hua Yu Tong Li Qing Guan Na Li Yang Chai Guang-Yu Zhang 《Chinese Physics B》 2026年第1期259-264,共6页
When stacking two-dimensional(2D)materials with a lattice mismatch and/or a small twist,moirésuperlattice emerges with fascinating electronic and optical properties.The fabrication of such stacked 2D materials us... When stacking two-dimensional(2D)materials with a lattice mismatch and/or a small twist,moirésuperlattice emerges with fascinating electronic and optical properties.The fabrication of such stacked 2D materials usually requires multiple transfer and stack processes,assisted by a certain transfer medium which needs to be removed afterwards,and it is very challenging to maintain pristine and clean surfaces/interfaces for these stacked structures.In this work,we report a facile direct bonding method for fabrication of twisted MoS_(2) bilayers with ultra-clean surfaces/interfaces.Novel interlayer interactions are revealed in the as-fabricated high-quality samples,leading to twist-angle related dispersion behavior of various Raman modes,such as layer breathing modes,shear modes and E_(2g)modes,as well as indirect bandgap excitons.Field-effect transistors(FETs)of twisted MoS_(2) bilayers also exhibit angle-dependent performance,which could be attributed to the band structure evolution.This facile method holds significance for the future integration of pre-designed multilayer 2D materials and paves a way to explore underlying physical mechanisms and potential applications. 展开更多
关键词 two-dimensional(2D)materials direct bonding moirésuperlattice twistronics
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Navigating physical activity research in complex terrains:Reflections on the challenges,opportunities,and future directions
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作者 Ding Ding 《Journal of Sport and Health Science》 2026年第3期3-5,共3页
In 2025,I had the honor of delivering keynote speeches at the conferences of the International Society for Diet and Activity Methods in Toronto,Canada,and the International Society of Behavioural Nutrition and Physica... In 2025,I had the honor of delivering keynote speeches at the conferences of the International Society for Diet and Activity Methods in Toronto,Canada,and the International Society of Behavioural Nutrition and Physical Activity in Auckland,Aotearoa,New Zealand.These opportunities prompted deep reflection on scientific research in general,and on physical activity and health research specifically. 展开更多
关键词 scientific research complex terrains future directions diet activity methods research challenges physical activity behavioural nutrition physical activity
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