检索结果-南通市图书馆

Ion and electron motions in the outer electron diffusion region of collisionless magnetic reconnection

Earth and Planetary Physics 2024年第3期8卷 472-478页

作者： Cong chang QuanMing lu San lu Kai Huang RongSheng wang Deep Space Exploration Laboratory School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences(CAS)Center for Excellence in Comparative Planetology CAS Key Laboratory of Geospace EnvironmentHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China

Two-dimensional particle-in-cell simulations are performed to study the coupling between ion and electron motions in collisionless magnetic reconnection.The electron diffusion region(EDR),where the electron motions are demagnetized,is found to have a two-layer structure:an inner EDR near the reconnection site and an outer EDR that is elongated to nearly 10 ion inertial lengths in the outflow direction.In the inner EDR,the speed of the electron outflow increases when the electrons move away from the X line.In the outer EDR,the speed of the electron outflow first increases and then decreases until the electrons reach the boundary of the outer EDR.In the boundary of the outer EDR,the magnetic field piles up and forms a depolarization front.From the perspective of the fluid,a force analysis on the formation of electron and ion outflows has also been investigated.Around the X line,the electrons are accelerated by the reconnection electric field in the out-of-plane direction.When the electrons move away from the X line,we find that the Lorentz force converts the direction of the accelerated electrons to the x direction,forming an electron outflow.Both electric field forces and electron gradient forces tend to drag the electron outflow.Ion acceleration along the x direction is caused by the Lorentz force,whereas the pressure gradient force tends to decelerate the ion outflow.Although these two terms are important,their effects on ions are almost offset.The Hall electric field force does positive work on ions and is not negligible.The ions are continuously accelerated,and the ion and electron outflow velocities are almost the same near the depolarization front.

关键词： collisionless magnetic reconnection electron diffusion region force analysis particle-in-cell simulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Organic near-infrared optoelectronic materials and devices:an overview

引用

Advanced Photonics 2024年第1期6卷 17-42页

作者： Zong-lu Che chang-Cun Yan Xue-Dong wang Liang-Sheng Liao Soochow University Institute of Functional Nano and Soft Materials(FUNSOM)Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSuzhouChina Soochow University College of ChemistryChemical Engineering and Materials ScienceJiangsu Engineering Laboratory of Novel Functional Polymeric MaterialsSuzhouChina Macao University of Science and Technology Macao Institute of Materials Science and EngineeringMacaoChina

Near-infrared(NIR)light has shown great potential for military and civilian applications owing to its advantages in the composition of sunlight,invisibility to human eyes,deeper penetration into biological tissues,and low optical loss in optical fibers.Therefore,organic optoelectronic materials that can absorb or emit NIR light have aroused great scientific interest in basic science and practical applications.Based on these NIR organic optoelectronic materials,NIR optoelectronic devices have been greatly improved in performance and application.In this review,the representative NIR organic optoelectronic materials used in organic solar cells,organic photodetectors,organic light-emitting diodes,organic lasers,and organic optical waveguide devices are briefly introduced,and the potential applications of each kind of device are briefly summarized.Finally,we summarize and take up the development of NIR organic optoelectronic materials and devices.

关键词： near-infrared organic optoelectronic materials organic solar cells organic light-emitting devices organic optical waveguides

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Collective Molecular Machines: Multidimensionality and Reconfigurability

引用

Nano-Micro Letters 2024年第8期16卷 309-340页

作者： Bin wang Yuan lu Department of Chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense research.Effective progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and informatics.However,individual molecular machines are only capable of producing nanometer work and generally have only a single functionality.In order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new paradigm.In this review,we comprehensively discuss recent developments in the collective behaviors of molecular machines.In particular,collective behavior is divided into two paradigms.One is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional materials.The other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale operations.We discuss design strategies for both modes and focus on the modulation of features and properties.Subsequently,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines.

关键词： Molecular machines Collective control Collective behaviors DNA Biomolecular motors

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Non-coding RNAs expression in SARS-CoV-2 infection:pathogenesis,clinical significance,and therapeutic targets

引用

Signal Transduction and Targeted Therapy 2024年第1期9卷 55-78页

作者： Xiaoxing Liu Wandi Xiong Maosen Ye Tangsheng lu Kai Yuan Suhua chang Ying Han Yongxiang wang Lin lu Yanping Bao Peking University Sixth Hospital Peking University Institute of Mental HealthNHC Key Laboratory of Mental Health(Peking University)National Clinical Research Center for Mental Disorders(Peking University Sixth Hospital)100191 BeijingChina Peking-Tsinghua Center for Life Sciences and PKU-IDG/McGovern Institute for Brain Research Peking University100871 BeijingChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan University570228 HaikouChina Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences&Yunnan Province KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesKunming Institute of ZoologyChinese Academy of Sciences650204 KunmingYunnanChina National Institute on Drug Dependence and Beijing Key Laboratory of Drug Dependence Peking UniversityBeijing 100191China Institute of Brain Science and Brain-inspired Research Shandong First Medical University&Shandong Academy of Medical Sciences250117 JinanShandongChina Department of Neurology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandongChina School of Public Health Peking University100191 BeijingChina

The coronavirus disease 2019(COVID-19)pandemic has been looming globally for three years,yet the diagnostic and treatment methods for COVID-19 are still undergoing extensive exploration,which holds paramount importance in mitigating future epidemics.Host non-coding RNAs(ncRNAs)display aberrations in the context of COVID-19.Specifically,microRNAs(miRNAs),long non-coding RNAs(lncRNAs),and circular RNAs(circRNAs)exhibit a close association with viral infection and disease progression.In this comprehensive review,an overview was presented of the expression profiles of host ncRNAs following SARS-CoV-2 invasion and of the potential functions in COVID-19 development,encompassing viral invasion,replication,immune response,and multiorgan deficits which include respiratory system,cardiac system,central nervous system,peripheral nervous system as well as long COVID.Furthermore,we provide an overview of several promising host ncRNA biomarkers for diverse clinical scenarios related to COVID-19,such as stratification biomarkers,prognostic biomarkers,and predictive biomarkers for treatment response.In addition,we also discuss the therapeutic potential of ncRNAs for COVID-19,presenting ncRNA-based strategies to facilitate the development of novel treatments.Through an in-depth analysis of the interplay between ncRNA and COVID-19 combined with our bioinformatic analysis,we hope to offer valuable insights into the stratification,prognosis,and treatment of COVID-19.

关键词： invasion therapeutic infection

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Stereodivergent synthesis ofα-fluoroα-azaarylγ-butyrolactones via cooperative copper and iridium catalysis

引用

Fundamental Research 2024年第1期4卷 77-85页

作者： Kui Tian Xin chang lu Xiao Xiu-Qin Dong Chun-Jiang wang College of Chemistry and Molecular Sciences Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan UniversityWuhan 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 230021China Suzhou Institute of Wuhan University Suzhou 215123China

The development of stereodivergent synthetic methods to access all four stereoisomers of biologically importantα-fluoroγ-butyrolactones containing vicinal stereocenters is of great importance and poses a formidable challenge owing to ring strain and steric hindrance.Herein,a novel asymmetric[3+2]annulation ofα-fluoroα-azaaryl acetates with vinylethylene carbonate was successfully developed through Cu/Ir-catalyzed cascade allylic alkylation/lactonization,affording a variety of enantioenrichedα-fluoroγ-butyrolactones bearing vicinal stereogenic centers with high reaction efficiency and excellent levels of both stereoselectivity and regioselectivity(up to 98%yield,generally>20:1 dr and>99%ee).Notably,all four stereoisomers of these pharmaceutically valuable molecules could be accessed individually via simple permutations of two enantiomeric catalysts.In addition,other azaaryl acetates bearingα-methyl,α-chlorine orα-phenyl group were tolerated well in this transformation.Reaction mechanistic investigations were conducted to explore the process of this bimetallic catalysis based on the results of reaction intermediates,isotopic labelling experiments,and kinetic studies.

关键词： Asymmetric catalysis α-Fluoroγ-butyrolactones Synergistic catalysis Cascade reaction Stereodivergent synthesis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Progress on the antiferromagnetic topological insulator MnBi2Te4

引用

National Science Review 2024年第2期11卷 33-49页

作者： Shuai Li Tianyu Liu chang Liu Yayu wang Hai-Zhou lu X.C.Xie Hefei National Laboratory International Center for Quantum Materials School of Physics Peking University Institute for Nanoelectronic Devices and Quantum Computing Fudan University Department of Physics Harbin Institute of Technology Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen Key Laboratory of Quantum Science and Engineering International Quantum Academy Beijing Academy of Quantum Information Sciences Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of Physics Renmin University of China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University Frontier Science Center for Quantum Information

Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed maTher physics. They represent a new class of materials exhibiting nontrivial topological phases,and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic orders.In particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predictions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research directions in this field are also discussed.

关键词： MnBi2Te4 magnetic topological insulator antiferromagnetic quantum anomalous Hall effect axion insulator

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Theoretical insights of the pharmaceutical compound fluoxetine in water:Role in direct photolysis and indirect photolysis by free radicals

引用

Journal of Environmental Sciences 2024年第8期142卷 269-278页

作者： Ying lu Se wang Yifan Shen School of Environmental Science and Engineering Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologyJiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlNanjing University of Information Science and TechnologyNanjing 210044China

The frequent detection of pharmaceutical compounds in the environment has led to a growing awareness,which may pose a major threat to the aquatic environment.In this study,photodegradation(direct and indirect photolysis)of two different dissociation states of fluoxetine(Flu)was investigated in water,mainly including the determination of photolytic transition states and products,and the mechanisms of indirect photodegradation with·OH,CO_(3)^(*-)and NO_(3)^(*).The main direct photolysis pathways are defluorination and C–C bond cleavage.In addition,the indirect photodegradation of Flu in water is mainly through the reactions with·OH and NO_(3)^(*),and the photodegradation reaction with CO_(3)^(*-)is relatively difficult to occur in the water environment.Our results provide a theoretical basis for understanding the phototransformation process of Flu in the water environment and assessing its potential risk.

关键词： Fluoxetine Photochemical mechanism Direct photolysis Free radical reaction DFT

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Divergent total synthesis of marine meroterpenoids(+)-dysidavarones A–C

引用

Chinese Chemical Letters 2024年第3期35卷 234-238页

作者： Qunlong Zhang Yang Kuang Le chang Jingyi Kang Bingjian wang Chuanke Chong Zhaoyong lu State Key Laboratory of Medicinal Chemical Biology College of PharmacyNankai UniversityTianjin 300350China

Here,we report a concise and divergent enantioselective total synthesis of marine sesquiterpene quinone meroterpenoids(+)-dysidavarones A–C(1–3)using predysidavarone 6 as a key common intermediate.The highly strained and bridged eight-membered carbocycle of predysidavarone 6 was constructed by a one-pot intermolecular alkylation and intramolecular arylation of Wieland–Miescher ketone derivative 11 and benzyl bromide 12.The total synthesis of(+)-dysidavarones A–C(1–3)was achieved from predysidavarone 6 in a divergent manner by a late-stage introduction of the ethoxy group,which reveals the possible source of the ethoxy group within(+)-dysidavarones A–C(1–3)and provides a late-stage modifiable route for the synthesis of dysidavarone analogs for further anti-cancer activity evaluation.

关键词： Total synthesis Natural product Dysidavarones A–C Sesquiterpene quinone Meroterpenoid

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Efficient electroreduction of nitrate via enriched active phases on copper-cobalt oxides

引用

Chinese Chemical Letters 2024年第4期35卷 204-209页

作者： Ling Fang Sha wang Shun lu Fengjun Yin Yujie Dai Lin chang Hong Liu Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China University of Chinese Academy of Sciences Beijing 100049China

Electrochemical conversion of nitrate(NO_(3)~-) to ammonia(NH_(3)) can target two birds with one stone well, in NO_(3)^(-)-containing sewage remediation and sustainable NH_(3) production. However, single metalbased catalysts are difficult to drive high-efficient NO_(3)~- removal due to the multi-electron transfer steps.Herein, we present a tandem catalyst with simple structure, Cu-Co binary metal oxides(Cu-Co-O), by engineering intermediate phases as catalytic active species for NO_(3)~- conversion. Electrochemical evaluation,X-ray photoelectron spectroscopy, and in situ Raman spectra together suggest that the newly-generated Cu-based phases was prone to NO_(3)~- to NO_(2)~- conversion, then NO_(2)~- was reduced to NH_(3) on Co-based species. At an applied potential of -1.1 V vs. saturated calomel electrode, the Cu-Co-O catalyst achieved NO_(3)~- -N removal of 90% and NH_(3) faradaic efficiency of 81% for 120 min in 100 m L of 50 mg/L NO_(3)~- -N,consuming only 0.69 k Wh/mol in a two-electrode system. This study provides a facile and efficient engineering strategy for developing high-performance catalysts for electrocatalytic nitrate conversion.

关键词： NO_(3)^(-)-containing sewage remediation Electrocatalytic reduction Copper-cobalt oxides Tandem reactivity Enriched active phases

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Population genomic data reveal low genetic diversity,divergence and local adaptation among threatened Reeves's Pheasant(Syrmaticus reevesii)

引用

Avian Research 2024年第1期15卷 1-11页

作者： Qi lu Pengcheng wang Jiang chang De Chen Shenghan Gao Jacob Hoglund Zhengwang Zhang Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing100875China Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjing210023China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing100101China Department of Ecology and Genetics Animal EcologyUppsala UniversityUppsalaSweden

Population genomic data could provide valuable information for conservation efforts;however,limited studies have been conducted to investigate the genetic status of threatened pheasants.Reeves’s Pheasant(Syrmaticus reevesii)is facing population decline,attributed to increases in habitat loss.There is a knowledge gap in understanding the genomic status and genetic basis underlying the local adaptation of this threatened bird.Here,we used population genomic data to assess population structure,genetic diversity,inbreeding patterns,and genetic divergence.Furthermore,we identified candidate genes linked with adaptation across the current distribution of Reeves’s Pheasant.The present study assembled the first de novo genome sequence of Reeves’s Pheasant and annotated 19,458 genes.We also sequenced 30 individuals from three populations(Dabie Mountain,Shennongjia,Qinling Mountain)and found that there was clear population structure among those populations.By comparing with other threatened species,we found that Reeves’s Pheasants have low genetic diversity.Runs of homozygosity suggest that the Shennongjia population has experienced serious inbreeding.The demographic history results indicated that three populations experienced several declines during the glacial period.Local adaptative analysis among the populations identified 241 candidate genes under directional selection.They are involved in a large variety of processes,including the immune response and pigmentation.Our results suggest that the three populations should be considered as three different conservation units.The current study provides genetic evidence for conserving the threatened Reeves’s Pheasant and provides genomic resources for global biodiversity management.

关键词： Conservation genetics Local adaptation Pheasant Whole-genome sequencing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：