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基于UPLC-QTOF-MS和网络药理学探讨平卧菊三七治疗高尿酸血症潜在作用机制
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作者 万丽莉 黄丽娟 +1 位作者 刘匡一 张凌云 《药品评价》 CAS 2024年第4期429-435,共7页
目的鉴定平卧菊三七入血化学成分,采用网络药理学方法探讨平卧菊三七治疗高尿酸血症潜在作用机制。方法通过超高效液相色谱-四级杆飞行时间串联质谱(UPLC-QTOF-MS)联用技术鉴定大鼠入血成分,利用TCMSP、Swiss Target Prediction、Gene-C... 目的鉴定平卧菊三七入血化学成分,采用网络药理学方法探讨平卧菊三七治疗高尿酸血症潜在作用机制。方法通过超高效液相色谱-四级杆飞行时间串联质谱(UPLC-QTOF-MS)联用技术鉴定大鼠入血成分,利用TCMSP、Swiss Target Prediction、Gene-Cards数据库获得入血成分及疾病作用靶点,并通过STRING数据库、Cytoscape软件筛选核心靶点并构建PPI网络图、“入血成分-交集靶点”图;运用DAVID平台进行基因本体(GO)功能富集及KEGG通路富集分析。结果测得平卧菊三七入血成分24个,共筛选得到13个核心靶点、162个生物过程、86条信号通路。结论平卧菊三七可能通过槲皮素、咖啡酸、芦丁、秦皮乙素等活性成分作用于STAT3、RELA、IL6、PTGS2等核心靶点来调控细胞增殖、迁移等多个生物学过程,从而协同发挥治疗高尿酸血症的作用。 展开更多
关键词 uplc-qtof-ms 网络药理学 平卧菊三七 高尿酸血症
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基于UPLC-QTOF-MS/MS的卷柏化学成分分析
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作者 温静 阎新佳 《天然产物研究与开发》 CAS CSCD 北大核心 2024年第10期1660-1669,共10页
利用超高效液相色谱-四级杆飞行时间串联质谱法(UPLC-QTOF-MS/MS)对中药卷柏的化学成分进行快速分析及鉴定。采用Agilent Poroshell 120 SB-Aq(2.7μm,2.1 mm×100 mm)色谱柱,以乙腈-0.1%甲酸水溶液为流动相,梯度洗脱,流速为0.4 mL/... 利用超高效液相色谱-四级杆飞行时间串联质谱法(UPLC-QTOF-MS/MS)对中药卷柏的化学成分进行快速分析及鉴定。采用Agilent Poroshell 120 SB-Aq(2.7μm,2.1 mm×100 mm)色谱柱,以乙腈-0.1%甲酸水溶液为流动相,梯度洗脱,流速为0.4 mL/min,进样量为3μL;选择电喷雾离子源分别在正、负离子模式下扫描分析,通过保留时间、精确相对分子质量和二级质谱裂解碎片,对所得成分的主要色谱峰进行鉴定。结果显示从卷柏中共鉴定出54个化学成分,主要包括双黄酮及黄酮类15个、炔酚类12个、酚酸类10个、苯丙素类5个、甾体类2个、萜类2个、氨基酸及肽类2个、酯类2个和其他类4个,并首次探讨炔酚类成分的裂解规律。该研究建立的UPLC-QTOF-MS/MS方法可以快速准确且较全面地分析鉴定卷柏中的化学成分,可为其质量控制及药效物质基础研究提供科学依据。 展开更多
关键词 卷柏 uplc-qtof-ms/MS 双黄酮类 炔酚类
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Progress on two-dimensional ferrovalley materials
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作者 李平 刘邦 +2 位作者 陈帅 张蔚曦 郭志新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期32-43,共12页
The electron's charge and spin degrees of freedom are at the core of modern electronic devices. With the in-depth investigation of two-dimensional materials, another degree of freedom, valley, has also attracted t... The electron's charge and spin degrees of freedom are at the core of modern electronic devices. With the in-depth investigation of two-dimensional materials, another degree of freedom, valley, has also attracted tremendous research interest. The intrinsic spontaneous valley polarization in two-dimensional magnetic systems, ferrovalley material, provides convenience for detecting and modulating the valley. In this review, we first introduce the development of valleytronics.Then, the valley polarization forms by the p-, d-, and f-orbit that are discussed. Following, we discuss the investigation progress of modulating the valley polarization of two-dimensional ferrovalley materials by multiple physical fields, such as electric, stacking mode, strain, and interface. Finally, we look forward to the future developments of valleytronics. 展开更多
关键词 ferrovalley valley polarization two-dimensional materials multi-field tunable
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Recent advances in two-dimensional photovoltaic devices
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作者 Haoyun Wang Xingyu Song +6 位作者 Zexin Li Dongyan Li Xiang Xu Yunxin Chen Pengbin Liu Xing Zhou Tianyou Zhai 《Journal of Semiconductors》 EI CAS CSCD 2024年第5期26-40,共15页
Two-dimensional(2D)materials have attracted tremendous interest in view of the outstanding optoelectronic properties,showing new possibilities for future photovoltaic devices toward high performance,high specific powe... Two-dimensional(2D)materials have attracted tremendous interest in view of the outstanding optoelectronic properties,showing new possibilities for future photovoltaic devices toward high performance,high specific power and flexibility.In recent years,substantial works have focused on 2D photovoltaic devices,and great progress has been achieved.Here,we present the review of recent advances in 2D photovoltaic devices,focusing on 2D-material-based Schottky junctions,homojunctions,2D−2D heterojunctions,2D−3D heterojunctions,and bulk photovoltaic effect devices.Furthermore,advanced strategies for improving the photovoltaic performances are demonstrated in detail.Finally,conclusions and outlooks are delivered,providing a guideline for the further development of 2D photovoltaic devices. 展开更多
关键词 two-dimensional materials photovoltaic devices PHOTODETECTORS solar cells HETEROSTRUCTURES
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Alternating spin splitting of electronic and magnon bands in two-dimensional altermagnetic materials
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作者 Qian Wang Da-Wei Wu +2 位作者 Guang-Hua Guo Meng-Qiu Long Yun-Peng Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期194-198,共5页
Unconventional antiferromagnetism dubbed as altermagnetism was first discovered in rutile structured magnets,which is featured by spin splitting even without the spin–orbital coupling effect.This interesting phenomen... Unconventional antiferromagnetism dubbed as altermagnetism was first discovered in rutile structured magnets,which is featured by spin splitting even without the spin–orbital coupling effect.This interesting phenomenon has been discovered in more altermagnetic materials.In this work,we explore two-dimensional altermagnetic materials by studying two series of two-dimensional magnets,including MF4 with M covering all 3d and 4d transition metal elements,as well as TS2 with T=V,Cr,Mn,Fe.Through the magnetic symmetry operation of RuF4 and MnS2,it is verified that breaking the time inversion is a necessary condition for spin splitting.Based on symmetry analysis and first-principles calculations,we find that the electronic bands and magnon dispersion experience alternating spin splitting along the same path.This work paves the way for exploring altermagnetism in two-dimensional materials. 展开更多
关键词 two-dimensional altermagnetic materials altermagnetism spin splitting first-principles calculations
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Unlocking the potential of ultra-thin two-dimensional antimony materials:Selective growth and carbon coating for efficient potassium-ion storage
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作者 Dongyu Zhang Zhaomin Wang +4 位作者 Yabin Shen Yeguo Zou Chunli Wang Limin Wang Yong Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期440-449,共10页
Antimony-based anodes have attracted wide attention in potassium-ion batteries due to their high theoretical specific capacities(∼660 mA h g^(-1))and suitable voltage platforms.However,severe capacity fading caused b... Antimony-based anodes have attracted wide attention in potassium-ion batteries due to their high theoretical specific capacities(∼660 mA h g^(-1))and suitable voltage platforms.However,severe capacity fading caused by huge volume change and limited ion transportation hinders their practical applications.Recently,strategies for controlling the morphologies of Sb-based materials to improve the electrochemical performances have been proposed.Among these,the two-dimensional Sb(2D-Sb)materials present excellent properties due to shorted ion immigration paths and enhanced ion diffusion.Nevertheless,the synthetic methods are usually tedious,and even the mechanism of these strategies remains elusive,especially how to obtain large-scale 2D-Sb materials.Herein,a novel strategy to synthesize 2D-Sb material using a straightforward solvothermal method without the requirement of a complex nanostructure design is provided.This method leverages the selective adsorption of aldehyde groups in furfural to induce crystal growth,while concurrently reducing and coating a nitrogen-doped carbon layer.Compared to the reported methods,it is simpler,more efficient,and conducive to the production of composite nanosheets with uniform thickness(3–4 nm).The 2D-Sb@NC nanosheet anode delivers an extremely high capacity of 504.5 mA h g^(-1) at current densities of 100 mA g^(-1) and remains stable for more than 200 cycles.Through characterizations and molecular dynamic simulations,how potassium storage kinetics between 2D Sb-based materials and bulk Sb-based materials are explored,and detailed explanations are provided.These findings offer novel insights into the development of durable 2D alloy-based anodes for next-generation potassium-ion batteries. 展开更多
关键词 ANTIMONY two-dimensional materials Selective growth Nitrogen-doped carbon Potassium-ion batteries
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Recent progress on valley polarization and valley-polarized topological states in two-dimensional materials
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作者 王斐 张亚玲 +2 位作者 杨文佳 张会生 许小红 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期16-31,共16页
Valleytronics, using valley degree of freedom to encode, process, and store information, may find practical applications in low-power-consumption devices. Recent theoretical and experimental studies have demonstrated ... Valleytronics, using valley degree of freedom to encode, process, and store information, may find practical applications in low-power-consumption devices. Recent theoretical and experimental studies have demonstrated that twodimensional(2D) honeycomb lattice systems with inversion symmetry breaking, such as transition-metal dichalcogenides(TMDs), are ideal candidates for realizing valley polarization. In addition to the optical field, lifting the valley degeneracy of TMDs by introducing magnetism is an efficient way to manipulate the valley degree of freedom. In this paper, we first review the recent progress on valley polarization in various TMD-based systems, including magnetically doped TMDs,intrinsic TMDs with both inversion and time-reversal symmetry broken, and magnetic TMD heterostructures. When topologically nontrivial bands are empowered into valley-polarized systems, valley-polarized topological states, namely valleypolarized quantum anomalous Hall effect can be realized. Therefore, we have also reviewed the theoretical proposals for realizing valley-polarized topological states in 2D honeycomb lattices. Our paper can help readers quickly grasp the latest research developments in this field. 展开更多
关键词 valley polarization valley-polarized topological states two-dimensional material
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Global dust density in two-dimensional complex plasma
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作者 赵逸真 刘松芬 +1 位作者 孔伟 杨芳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期445-450,共6页
The driven-dissipative Langevin dynamics simulation is used to produce a two-dimensional(2D) dense cloud, which is composed of charged dust particles trapped in a quadratic potential. A 2D mesh grid is built to analyz... The driven-dissipative Langevin dynamics simulation is used to produce a two-dimensional(2D) dense cloud, which is composed of charged dust particles trapped in a quadratic potential. A 2D mesh grid is built to analyze the center-to-wall dust density. It is found that the local dust density in the outer region relative to that of the inner region is more nonuniform,being consistent with the feature of quadratic potential. The dependences of the global dust density on equilibrium temperature, particle size, confinement strength, and confinement shape are investigated. It is found that the particle size, the confinement strength, and the confinement shape strongly affect the global dust density, while the equilibrium temperature plays a minor effect on it. In the direction where there is a stronger confinement, the dust density gradient is bigger. 展开更多
关键词 dust particles quadratic potential two-dimensional mesh grid
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Boosting MA-based two-dimensional Ruddlesden-Popper perovskite solar cells by incorporating a binary spacer
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作者 Xue Dong Yinhao Tang +10 位作者 Yiqun Li Xin Li Yuzhen Zhao Wenqi Song Fangmin Wang Shudong Xu Yipeng Zhou Chenxin Ran Zongcheng Miao Lin Song Zhongbin Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期348-356,I0008,共10页
Two-dimensional Ruddlesden-Popper(2DRP)perovskite exhibits excellent stability in perovskite solar cells(PSCs)due to introducing hydrophobic long-chain organic spacers.However,the poor charge transporting property of ... Two-dimensional Ruddlesden-Popper(2DRP)perovskite exhibits excellent stability in perovskite solar cells(PSCs)due to introducing hydrophobic long-chain organic spacers.However,the poor charge transporting property of bulky organic cation spacers limits the performance of 2DRP PSCs.Inspired by the Asite cation alloying strategy in 3D perovskites,2DRP perovskites with a binary spacer can promote charge transporting compared to the unary spacer counterparts.Herein,the superior MA-based 2DRP perovskite films with a binary spacer,including 3-guanidinopropanoic acid(GPA)and 4-fluorophenethylamine(FPEA)are realized.These films(GPA_(0.85)FPEA_(0.15))_(2)MA_(4)Pb_5I_(16)show good morphology,large grain size,decreased trap state density,and preferential orientation of the as-prepared film.Accordingly,the present 2DRP-based PSC with the binary spacer achieves a remarkable efficiency of 18.37%with a V_(OC)of1.15 V,a J_(SC)of 20.13 mA cm^(-2),and an FF of 79.23%.To our knowledge,the PCE value should be the highest for binary spacer MA-based 2DRP(n≤5)PSCs to date.Importantly,owing to the hydrophobic fluorine group of FPEA and the enhanced interlayer interaction by FPEA,the unencapsulated 2DRP PSCs based on binary spacers exhibit much excellent humidity stability and thermal stability than the unary spacer counterparts. 展开更多
关键词 Perovskite solar cells two-dimensional Ruddlesden-Popper perovskite Binary spacers Stability
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Low-frequency hybridized excess vibrations of two-dimensional glasses
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作者 付立存 郑一鸣 王利近 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期550-555,共6页
One hallmark of glasses is the existence of excess vibrational modes at low frequenciesωbeyond Debye’s prediction.Numerous studies suggest that understanding low-frequency excess vibrations could help gain insight i... One hallmark of glasses is the existence of excess vibrational modes at low frequenciesωbeyond Debye’s prediction.Numerous studies suggest that understanding low-frequency excess vibrations could help gain insight into the anomalous mechanical and thermodynamic properties of glasses.However,there is still intensive debate as to the frequency dependence of the population of low-frequency excess vibrations.In particular,excess modes could hybridize with phonon-like modes and the density of hybridized excess modes has been reported to follow D_(exc)(ω)~ω^(2)in 2D glasses with an inverse power law potential.Yet,the universality of the quadratic scaling remains unknown,since recent work suggested that interaction potentials could influence the scaling of the vibrational spectrum.Here,we extend the universality of the quadratic scaling for hybridized excess modes in 2D to glasses with potentials ranging from the purely repulsive soft-core interaction to the hard-core one with both repulsion and attraction as well as to glasses with significant differences in density or interparticle repulsion.Moreover,we observe that the number of hybridized excess modes exhibits a decrease in glasses with higher density or steeper interparticle repulsion,which is accompanied by a suppression of the strength of the sound attenuation.Our results indicate that the density bears some resemblance to the repulsive steepness of the interaction in influencing low-frequency properties. 展开更多
关键词 density of states vibrational modes sound attenuation two-dimensional glasses
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Anomalous valley Hall effect in two-dimensional valleytronic materials
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作者 陈洪欣 原晓波 任俊峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期2-14,共13页
The anomalous valley Hall effect(AVHE)can be used to explore and utilize valley degrees of freedom in materials,which has potential applications in fields such as information storage,quantum computing and optoelectron... The anomalous valley Hall effect(AVHE)can be used to explore and utilize valley degrees of freedom in materials,which has potential applications in fields such as information storage,quantum computing and optoelectronics.AVHE exists in two-dimensional(2D)materials possessing valley polarization(VP),and such 2D materials usually belong to the hexagonal honeycomb lattice.Therefore,it is necessary to achieve valleytronic materials with VP that are more readily to be synthesized and applicated experimentally.In this topical review,we introduce recent developments on realizing VP as well as AVHE through different methods,i.e.,doping transition metal atoms,building ferrovalley heterostructures and searching for ferrovalley materials.Moreover,2D ferrovalley systems under external modulation are also discussed.2D valleytronic materials with AVHE demonstrate excellent performance and potential applications,which offer the possibility of realizing novel low-energy-consuming devices,facilitating further development of device technology,realizing miniaturization and enhancing functionality of them. 展开更多
关键词 anomalous valley Hall effect valley polarization valleytronics two-dimensional materials
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Multi-party semi-quantum private comparison protocol of size relation based on two-dimensional Bell states
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作者 Bing Wang Li-Hua Gong San-Qiu Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期184-192,共9页
Currently,all quantum private comparison protocols based on two-dimensional quantum states can only compare equality,via using high-dimensional quantum states that it is possible to compare the size relation in existi... Currently,all quantum private comparison protocols based on two-dimensional quantum states can only compare equality,via using high-dimensional quantum states that it is possible to compare the size relation in existing work.In addition,it is difficult to manipulate high-dimensional quantum states under the existing conditions of quantum information processing,leading to low practicality and engineering feasibility of protocols for comparing size relation.Considering this situation,we propose an innovative protocol.The proposed protocol can make size comparison by exploiting more manageable two-dimensional Bell states,which significantly enhances its feasibility with current quantum technologies.Simultaneously,the proposed protocol enables multiple participants to compare their privacies with the semi-quantum model.The communication process of the protocol is simulated on the IBM Quantum Experience platform to verify its effectiveness.Security analysis shows that the proposed protocol can withstand common attacks while preserving the privacies of all participants.Thus,the devised protocol may provide an important reference for implementation of quantum private size comparison protocols. 展开更多
关键词 two-dimensional Bell state size relation multi-party semi-quantum private comparison
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Emerging two-dimensional Mo-based materials for rechargeable metal-ion batteries:Advances and perspectives
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作者 Qingqing Ruan Yuehua Qian +2 位作者 Mengda Xue Lingyun Chen Qichun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期487-518,I0012,共33页
With the rapid development of rechargeable metal-ion batteries(MIBs)with safety,stability and high energy density,significant efforts have been devoted to exploring high-performance electrode materials.In recent years... With the rapid development of rechargeable metal-ion batteries(MIBs)with safety,stability and high energy density,significant efforts have been devoted to exploring high-performance electrode materials.In recent years,two-dimensional(2D)molybdenum-based(Mo-based)materials have drawn considerable attention due to their exceptional characteristics,including low cost,unique crystal structure,high theoretical capacity and controllable chemical compositions.However,like other transition metal compounds,Mo-based materials are facing thorny challenges to overcome,such as slow electron/ion transfer kinetics and substantial volume changes during the charge and discharge processes.In this review,we summarize the recent progress in developing emerging 2D Mo-based electrode materials for MIBs,encompassing oxides,sulfides,selenides,carbides.After introducing the crystal structure and common synthesis methods,this review sheds light on the charge storage mechanism of several 2D Mo-based materials by various advanced characterization techniques.The latest achievements in utilizing 2D Mo-based materials as electrode materials for various MIBs(including lithium-ion batteries(LIBs),sodium-ion batteries(SIBs)and zinc-ion batteries(ZIBs))are discussed in detail.Afterwards,the modulation strategies for enhancing the electrochemical performance of 2D Mo-based materials are highlighted,focusing on heteroatom doping,vacancies creation,composite coupling engineering and nanostructure design.Finally,we present the existing challenges and future research directions for 2D Mo-based materials to realize high-performance energy storage systems. 展开更多
关键词 Molybdenum-based materials two-dimensional materials Lithium-ion batteries Sodium-ion batteries Zinc-ion batteries
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Image segmentation of exfoliated two-dimensional materials by generative adversarial network-based data augmentation
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作者 程晓昱 解晨雪 +6 位作者 刘宇伦 白瑞雪 肖南海 任琰博 张喜林 马惠 蒋崇云 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期112-117,共6页
Mechanically cleaved two-dimensional materials are random in size and thickness.Recognizing atomically thin flakes by human experts is inefficient and unsuitable for scalable production.Deep learning algorithms have b... Mechanically cleaved two-dimensional materials are random in size and thickness.Recognizing atomically thin flakes by human experts is inefficient and unsuitable for scalable production.Deep learning algorithms have been adopted as an alternative,nevertheless a major challenge is a lack of sufficient actual training images.Here we report the generation of synthetic two-dimensional materials images using StyleGAN3 to complement the dataset.DeepLabv3Plus network is trained with the synthetic images which reduces overfitting and improves recognition accuracy to over 90%.A semi-supervisory technique for labeling images is introduced to reduce manual efforts.The sharper edges recognized by this method facilitate material stacking with precise edge alignment,which benefits exploring novel properties of layered-material devices that crucially depend on the interlayer twist-angle.This feasible and efficient method allows for the rapid and high-quality manufacturing of atomically thin materials and devices. 展开更多
关键词 two-dimensional materials deep learning data augmentation generating adversarial networks
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Single-cell manipulation by two-dimensional micropatterning
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作者 Xuehe Ma Haimei Zhang +7 位作者 Shiyu Deng Qiushuo Sun Qingsong Hu Yuhang Pan Fen Hu Imshik Lee Fulin Xing Leiting Pan 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期45-59,共15页
Cells are highly sensitive to their geometrical and mechanical microenvironment that directly regulate cell shape,cytoskeleton and organelle,as well as the nucleus morphology and genetic expression.The emerging two-di... Cells are highly sensitive to their geometrical and mechanical microenvironment that directly regulate cell shape,cytoskeleton and organelle,as well as the nucleus morphology and genetic expression.The emerging two-dimensional micropatterning techniques offer powerful tools to construct controllable and well-organized microenvironment for single-cell level investigations with qualitative analysis,cellular standardization,and in vivo environment mimicking.Here,we provide an overview of the basic principle and characteristics of the two most widely-used micropatterning techniques,including photolithographic micropatterning and soft lithography micropatterning.Moreover,we summarize the application of micropatterning technique in controlling cytoskeleton,cell migration,nucleus and gene expression,as well as intercellular communication. 展开更多
关键词 two-dimensional micropatterning CYTOSKELETON cell migration extracellular matrix intercellular communication gene expression
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Magnetic proximity effect in the two-dimensional ε-Fe_(2)O_(3)/NbSe_(2)heterojunction
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作者 车冰玉 胡国静 +17 位作者 朱超 郭辉 吕森浩 刘轩冶 吴康 赵振 潘禄禄 祝轲 齐琦 韩烨超 林晓 李子安 申承民 鲍丽宏 刘政 周家东 杨海涛 高鸿钧 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期492-497,共6页
Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie te... Two-dimensional(2D)magnet/superconductor heterostructures can promote the design of artificial materials for exploring 2D physics and device applications by exotic proximity effects.However,plagued by the low Curie temperature and instability in air,it is hard to realize practical applications for the reported layered magnetic materials at present.In this paper,we developed a space-confined chemical vapor deposition method to synthesize ultrathin air-stable ε-Fe_(2)O_(3) nanosheets with Curie temperature above 350 K.The ε-Fe_(2)O_(3)/NbSe_(2) heterojunction was constructed to study the magnetic proximity effect on the superconductivity of the NbSe_(2) multilayer.The electrical transport results show that the subtle proximity effect can modulate the interfacial spin–orbit interaction while undegrading the superconducting critical parameters.Our work paves the way to construct 2D heterojunctions with ultrathin nonlayered materials and layered van der Waals(vdW)materials for exploring new physical phenomena. 展开更多
关键词 two-dimensional heterojunctions magnetic proximity effect non-layered magnetic nanosheet spin-orbit interaction
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Two-Dimensional Perovskite Single Crystals for High-Performance X-ray Imaging and Exploring MeV X-ray Detection
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作者 Xieming Xu Yiheng Wu +5 位作者 Yi Zhang Xiaohui Li Fang Wang Xiaoming Jiang Shaofan Wu Shuaihua Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期139-146,共8页
Scintillation semiconductors play increasingly important medical diagnosis and industrial inspection roles.Recently,two-dimensional(2D)perovskites have been shown to be promising materials for medical X-ray imaging,bu... Scintillation semiconductors play increasingly important medical diagnosis and industrial inspection roles.Recently,two-dimensional(2D)perovskites have been shown to be promising materials for medical X-ray imaging,but they are mostly used in low-energy(≤130 keV)regions.Direct detection of MeV X-rays,which ensure thorough penetration of the thick shell walls of containers,trucks,and aircraft,is also highly desired in practical industrial applications.Unfortunately,scintillation semiconductors for high-energy X-ray detection are currently scarce.Here,This paper reports a 2D(C_(4)H_(9)NH_(3))_(2)PbBr_(4)single crystal with outstanding sensitivity and stability toward X-ray radiation that provides an ultra-wide detectable X-ray range of between 8.20 nGy_(air)s^(-1)(50 keV)and 15.24 mGy_(air)s^(-1)(9 MeV).The(C_(4)H_(9)NH_(3))_(2)PbBr_(4)single-crystal detector with a vertical structure is used for high-performance X-ray imaging,delivering a good spatial resolution of 4.3 Ip mm^(-1)in a plane-scan imaging system.Low ionic migration in the 2D perovskite enables the vertical device to be operated with hundreds of keV to MeV X-ray radiation at high bias voltages,leading to a sensitivity of 46.90μC Gy_(air)-1 cm^(-2)(-1.16 Vμm^(-1))with 9 MeV X-ray radiation,demonstrating that 2D perovskites have enormous potential for high-energy industrial applications. 展开更多
关键词 MeV X-ray detection single-crystal X-ray detectors two-dimensional perovskites X-ray imaging
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Stacking-dependent exchange bias in two-dimensional ferromagnetic/antiferromagnetic bilayers
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作者 李慧平 潘帅唯 +2 位作者 王喆 向斌 朱文光 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期708-714,共7页
A clear microscopic understanding of exchange bias is crucial for its application in magnetic recording, and further progress in this area is desired. Based on the results of our first-principles calculations and Mont... A clear microscopic understanding of exchange bias is crucial for its application in magnetic recording, and further progress in this area is desired. Based on the results of our first-principles calculations and Monte Carlo simulations,we present a theoretical proposal for a stacking-dependent exchange bias in two-dimensional compensated van der Waals ferromagnetic/antiferromagnetic bilayer heterostructures. The exchange bias effect emerges in stacking registries that accommodate inhomogeneous interlayer magnetic interactions between the ferromagnetic layer and different spin sublattices of the antiferromagnetic layer. Moreover, the on/off switching and polarity reversal of the exchange bias can be achieved by interlayer sliding, and the strength can be modulated using an external electric field. Our findings push the limits of exchange bias systems to extreme bilayer thickness in two-dimensional van der Waals heterostructures, potentially stimulating new experimental investigations and applications. 展开更多
关键词 exchange bias two-dimensional ferromagnetic/antiferromagnetic bilayers asymmetric magnetic interaction
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Two-Dimensional Materials for Highly Efficient and Stable Perovskite Solar Cells
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作者 Xiangqian Shen Xuesong Lin +5 位作者 Yong Peng Yiqiang Zhang Fei Long Qifeng Han Yanbo Wang Liyuan Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期176-212,共37页
Perovskite solar cells(PSCs)offer low costs and high power conversion efficiency.However,the lack of long-term stability,primarily stemming from the interfacial defects and the sus-ceptible metal electrodes,hinders th... Perovskite solar cells(PSCs)offer low costs and high power conversion efficiency.However,the lack of long-term stability,primarily stemming from the interfacial defects and the sus-ceptible metal electrodes,hinders their practical application.In the past few years,two-dimensional(2D)materials(e.g.,graphene and its derivatives,transitional metal dichalcogenides,MXenes,and black phosphorus)have been identified as a promising solution to solving these problems because of their dangling bond-free surfaces,layer-dependent electronic band structures,tunable functional groups,and inherent compactness.Here,recent progress of 2D material toward efficient and stable PSCs is summarized,including its role as both interface materials and electrodes.We discuss their beneficial effects on perovskite growth,energy level alignment,defect passivation,as well as blocking external stimulus.In particular,the unique properties of 2D materials to form van der Waals heterojunction at the bottom interface are emphasized.Finally,perspectives on the further development of PSCs using 2D materials are provided,such as designing high-quality van der Waals heterojunction,enhancing the uniformity and coverage of 2D nanosheets,and developing new 2D materials-based electrodes. 展开更多
关键词 Perovskite solar cells two-dimensional materials Interface engineering Van der Waals heterojunction Electrodes
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Automatic modulation recognition of radiation source signals based on two-dimensional data matrix and improved residual neural network
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作者 Guanghua Yi Xinhong Hao +3 位作者 Xiaopeng Yan Jian Dai Yangtian Liu Yanwen Han 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期364-373,共10页
Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive radio.However,the AMR of radiation source signals at low SNRs still faces a great challenge.Therefore,the ... Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive radio.However,the AMR of radiation source signals at low SNRs still faces a great challenge.Therefore,the AMR method of radiation source signals based on two-dimensional data matrix and improved residual neural network is proposed in this paper.First,the time series of the radiation source signals are reconstructed into two-dimensional data matrix,which greatly simplifies the signal preprocessing process.Second,the depthwise convolution and large-size convolutional kernels based residual neural network(DLRNet)is proposed to improve the feature extraction capability of the AMR model.Finally,the model performs feature extraction and classification on the two-dimensional data matrix to obtain the recognition vector that represents the signal modulation type.Theoretical analysis and simulation results show that the AMR method based on two-dimensional data matrix and improved residual network can significantly improve the accuracy of the AMR method.The recognition accuracy of the proposed method maintains a high level greater than 90% even at -14 dB SNR. 展开更多
关键词 Automatic modulation recognition Radiation source signals two-dimensional data matrix Residual neural network Depthwise convolution
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