检索结果-南通市图书馆

Superconducting,Topological,and Transport Properties of Kagome Metals CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)

Research 2024年第2期2023卷 753-762页

作者： Xin-wei Yi zheng-wei Liao Jing-Yang You Bo Gu Gang Su School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Faculty of ScienceNational University of Singapore117551Singapore Kavli Institute for Theoretical Sciences and CAS Center for Excellence in Topological Quantum ComputationUniversity of Chinese Academy of SciencesBeijing 100190China

The recently discovered ATi_(3)Bi_(5)(A=Cs,Rb)exhibit intriguing quantum phenomena including superconductivity,electronic nematicity,and abundant topological ***_(3)Bi_(5)present promising platforms for studying kagome superconductivity,band topology,and charge orders in parallel with *** this work,we comprehensively analyze various properties of ATi_(3)Bi_(5)covering superconductivity under pressure and doping,band topology under pressure,thermal conductivity,heat capacity,electrical resistance,and spin Hall conductivity(SHC)using first-principles *** superconducting transition temperature(Tc)of CsTi_(3)Bi_(5)and RbTi_(3)Bi_(5)at ambient pressure are about 1.85 and 1.92 *** subject to pressure,Tc of CsTi_(3)Bi_(5)exhibits a special valley and dome shape,which arises from quasi-two-dimensional compression to three-dimensional isotropic compression within the context of an overall decreasing ***,Tc of RbTi_(3)Bi_(5)can be effectively enhanced up to 3.09 K by tuning the kagome van Hove singularities(VHSs)and flat band through *** can also induce abundant topological surface states at the Fermi energy(EF)and tune VHSs across ***,our transport calculations are in excellent agreement with recent experiments,confirming the absence of charge density ***,SHC of CsTi_(3)Bi_(5)can reach up to 226h·(e·Ω·cm)^(-1)at *** work provides a timely and detailed analysis of the rich physical properties for ATi_(3)Bi_(5),offering valuable insights for further experimental verifications and investigations in this field.

关键词： doping superconductivity conductivity

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

Solid-state Circuit Breaker Based on Cascaded Normally-on SiC JFETs for Medium-voltage DC Distribution Networks

引用

Protection and Control of Modern Power Systems 2024年第2期9卷 32-46页

作者： Dong He Haohui zhou zheng Lan wei Wang Jinhui zeng Xueping Yu z.John Shen Chongqing University of Posts and Telecommunications ChongqingChina Henan Polytechnic University JiaozuoChina College of Electrical and Information Engineering Hunan University of TechnologyZhuzhou 412007China Hunan University ChangshaChina College of Electrical and Information Engineering Hunan UniversityChangshaChina College of Electrical Engineering Three Gorges University Rensselaer Polytechnic Institute TroyNYUSA

Solid-state circuit breakers(SSCBs)are critical components in the protection of medium-voltage DC distribution networks to facilitate arc-free,fast and reliable isolation of DC ***,limited by the capacity of a single semiconductor device,using semi-conductor-based SSCBs at high voltage is *** study presents the details of a 1.5 kV,63 A medi-um-voltage SSCB,composed primarily of a solid-state switch based on three cascaded normally-on silicon car-bide(SiC)junction field-effect transistors(JFETs)and a low-cost programmable gate drive *** and static voltage sharing among the cascaded SiC JFETs of the SSCB during fault isolation is realized using the pro-posed gate drive *** selection conditions for the key parameters of the SSCB gate driver are also ***,an improved pulse-width modulation cur-rent-limiting protection solution is proposed to identify the permanent overcurrent and transient inrush current associated with capacitive load startup in a DC distribu-tion *** the developed SSCB prototype and the fault test system,experimental results are obtained to validate the fault response performance of the *** Terms—Solid-state circuit breaker,DC distribu-tion network,SiC JFET,voltage balancing,inrush current.

关键词： Solid-state circuit breaker DC distribu-tion network SiC JFET voltage balancing inrush current

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

Preparation and characterization of Rb-doped TiO_(2) powders for photocatalytic applications

引用

Rare Metals 2024年第2期43卷 555-561页

作者： Lu Jia Li-Mei Yang wei Wang Song-Tao Huang zheng Xu National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous MetalsBeijing100088China

TiO_(2)nanoparticles doped with different concentrations of Rb were prepared by sol–gel *** crystal structures of samples were characterized by X-ray diffraction(XRD)and transmission electron microscopy(TEM).It was confirmed by the Rietveld refinement method that the as-prepared samples crystallize in anatase phase and Rb doping induces expansion and distortion of the crystal *** with the pure TiO_(2),the Rb-doped nanoparticles have smaller crystal size and better *** rate of methylene blue was used to evaluate the photocatalytic activity of Rb–TiO_(2).It indicated that doping Rb into TiO_(2)can effectively improve the photocatalytic activity of TiO_(2)and the mechanisms were discussed in *** using the sample doped with 0.20%Rb,methylene blue degraded with the fastest rate(97%within 60 min).

关键词： Rb doping TiO_(2) Photocatalysis Sol-gel

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

Optical Extinctions of Inter-Arm Molecular Clouds in M31:A Pilot Study for the Upcoming CSST Observations

引用

Research in Astronomy and Astrophysics 2024年第6期24卷 323-333页

作者： Cailing Chen zheng zheng Chao-wei Tsai Sihan Jiao Jing Tang Jingwen Wu Di Li Yun zheng Linjing Feng Yujiao Yang Yuan Liang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China zhejiang Lab Hangzhou 311121China

Recent submillimeter dust thermal emission observations have unveiled a significant number of inter-arm massive molecular clouds in ***,the effectiveness of this technique is limited to its sensitivity,making it challenging to study more distant *** study introduces an alternative approach,utilizing optical extinctions derived from space-based telescopes,with a focus on the forthcoming China Space Station Telescope(CSST).We first demonstrate the capability of this method by constructing dust extinction maps for 17 inter-arm massive molecular clouds in M31 using the Panchromatic Hubble Andromeda Treasury *** analysis reveals that inter-arm massive molecular clouds with an optical extinction(A_(V)) greater than 1.6 mag exhibit a notable A_(V) excess,facilitating their *** majority of these inter-arm massive molecular clouds show an A_(V) around 1 mag,aligning with measurements from our JCMT *** validation using a mock CSST RGB star catalog confirms the method's *** show that the derived A_(V)values using CSST z and y photometries align more closely with the input *** clouds with A_(V)> 1.6 mag can also be identified using the CSST mock *** thus claim that future CSST observation clouds provide an effective way for the detection of inter-arm massive molecular clouds with significant optical extinction in nearby galaxies.

关键词： infrared:stars ISM:clouds Galaxy:structure

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

Priming of the Cells： Hypoxic Preconditioning for Stem Cell Therapy

引用

Chinese Medical Journal 2017年第19期130卷 2361-2374页

作者： zheng z wei Yan-Bing zhu James Y zhang Myles R McCrary Song Wang Yong-Bo zhang Shan-Ping Yu Ling wei Department of Neurology Beijing Friendship Hospital Capital Medical University Beijing 100050 China Experimental and Translational Research Center Beijing Friendship Hospital Capital Medical University Beijing 100050 China Department of Anesthesiology Emory University School of Medicine Atlanta Georgia 30322 USA

Objective： Stem cell-based therapies are promising in regenerative medicine for protecting and repairing damaged brain tissues after injury or in the context of chronic diseases. Hypoxia can induce physiological and pathological responses. A hypoxic insult might act as a double-edged sword, it induces cell death and brain damage, but on the other hand, sublethal hypoxia can trigger an adaptation response called hypoxic preconditioning or hypoxic tolerance that is of immense importance for the survival of cells and tissues. Data Sources： This review was based on articles published in PubMed databases up to August 16, 2017, with the following keywords：＂stem cells,＂＂hypoxic preconditioning,＂＂ischemic preconditioning,＂ and ＂cell transplantation.＂Study Selection： Original articles and critical reviews on the topics were selected. Results： Hypoxic preconditioning has been investigated as a primary endogenous protective mechanism and possible treatment against ischemic injuries. Many cellular and molecular mechanisms underlying the protective effects of hypoxic preconditioning have been identified. Conclusions： In cell transplantation therapy, hypoxic pretreatment of stem cells and neural progenitors markedly increases the survival and regenerative capabilities of these cells in the host environment, leading to enhanced therapeutic effects in various disease models. Regenerative treatments can mobilize endogenous stem cells for neurogenesis and angiogenesis in the adult brain. Furthermore, transplantation of stem cells/neural progenitors achieves therapeutic benefits via cell replacement and/or increased trophic support. Combinatorial approaches of cell-based therapy with additional strategies such as neuroprotective protocols, anti-inflammatory treatment, and rehabilitation therapy can significantly improve therapeutic benefits. In this review, we will discuss the recent progress regarding cell types and applications in regenerative medicine as well as future applicatio

关键词： Angiogenesis Factor Cell Transplantation Endogenous Stem Cells Genome Editing Hypoxia Hypoxic Preconditioning Induced Pluripotent Stem Cells Neurological Disorders Tumor

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

Granger causal representation learning for groups of time series

引用

Science China(Information Sciences) 2024年第5期67卷 56-68页

作者： Ruichu CAI Yunjin WU Xiaokai HUANG wei CHEN Tom z.J.FU zhifeng HAO School of Computer Science Guangdong University of Technology Peng Cheng Laboratory College of Science Shantou University

Discovering causality from multivariate time series is an important but challenging *** existing methods focus on estimating the Granger causal structures among multivariate time series,while ignoring the prior knowledge of these time series, e.g., the group of the time series. Focusing on discovering the Granger causal structures among groups of time series, we propose a Granger causal representation learning method to solve this problem. First, we use the multiset canonical correlation analysis method to learn the Granger causal representation of each group of time series. Then, we model the Granger causal relationships among the learned Granger causal representations using a recurrent neural network with temporal information. Finally, we formulate the above two stages into one unified optimization problem, which is efficiently solved using the augmented Lagrangian method. We conduct extensive experiments on synthetic and real-world datasets to validate the correctness and effectiveness of the proposed method.

关键词： Granger causal discovery Granger causal representation learning time series data recurrent neural network multiset canonical correlation analysis

来源：

同方期刊数据库

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

Composition characterization and transformation mechanism of dissolved organic phosphorus in wastewater treatment using 31P NMR spectroscopy

引用

Frontiers of Environmental Science & Engineering 2024年第3期18卷 103-113页

作者： Yuting zhang wei Shang SoonThiam Khu Xingcan zheng Yongli Sun Pengfeng Li Miao Gu Wen-an zhang Huanmei Ma National Engineering Research Center For Urban Water&Wastewater North China Municipal Engineering Design&Research Institute Co.Ltd.Tianjin 300381China School of Environment Science&Engineering Tianjin UniversityTianjin 300350China

The migration and transformation of phosphorus components in wastewater treatment plants(WWTPs)play a crucial role in the convergence and circulation of ***,the composition and variation of dissolved organic phosphorus(DOP)in WWTPs were unclear because of its complex nature,hindering its efficient *** this study,the DOP species and their transformation during the treatment process in WWTP were comprehensively ***,two enrichment methods were assessed for their effectiveness at facilitating wastewater analysis:lyophilization and aluminum salt *** salt precipitation was found to be better because its application allowed 31P nuclear magnetic resonance(31P NMR)spectroscopy to identify more species in the secondary effluent:orthophosphate(Ortho-P)(81.1%–89.3%of the dissolved total phosphorus),pyrophosphates(Pyro-P)(0%–2.3%),orthophosphate monoesters(Mono-P)(7.0%–10.77%),orthophosphate diesters(Di-P)(1.0%–2.96%),and phosphonate(Phos-P)(1.7%–5.16%).Furthermore,the variation and transformation mechanism of phosphorus,particularly those of DOP,during the entire sewage-treatment process were *** the treatment steps,biological treatment combined tertiary treatment achieved better DOP removal ***,biological treatment mainly removed Mono-P and Di-P with removal efficiencies of 33.3%and 41.7%compared with the effluent of the grit ***-P has higher bioavailability and is more easily converted and utilized by microorganisms than ***,Phos-P,with low bioavailability,was hardly utilized by microorganisms,which showed only 18.4%removal efficiency in biological *** tertiary treatment,coagulation process exhibited higher removal ability of Ortho-P(69.1%)and partial removal efficiencies of DOP,resulting in an increase in the DOP proportion in *** addition,Phos-P could not be effectively removed through the biological treatment and was only partially reduced via the adsorption pro

关键词： Municipal wastewater Dissolved organic phosphorus Composition Transformation 31P nuclear magnetic resonance

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

Electromagnetic Performance Analysis of Variable Flux Memory Machines with Series-magnetic-circuit and Different Rotor Topologies

引用

CES Transactions on Electrical Machines and Systems 2024年第1期8卷 3-11页

作者： Qiang wei z.Q.zhu Yan Jia Jianghua Feng Shuying Guo Yifeng Li Shouzhi Feng Department of Electronic and Electrical Engineering The University of SheffieldSheffield S13JDU.K. IEEE the CRRC zhuzhou Institute Company Ltd. Zhuzhou 412001China

In this paper,the electromagnetic performance of variable flux memory(VFM)machines with series-magnetic-circuit is investigated and compared for different rotor *** on a V-type VFM machine,five topologies with different interior permanent magnet(IPM)arrangements are evolved and optimized under same *** on two-dimensional(2-D)finite element(FE)method,their electromagnetic performance at magnetization and demagnetization states is *** reveals that the iron bridge and rotor lamination region between constant PM(CPM)and variable PM(VPM)play an important role in torque density and flux regulation(FR)***,the global efficiency can be improved in VFM machines by adjusting magnetization state(MS)under different operating conditions.

关键词： Memory machine Permanent magnet Rotor topologies Series magnetic circuit Variable flux

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

Universal transfer of full-class metal electrodes for barrier-free two-dimensional semiconductor contacts

引用

InfoMat 2024年第1期6卷 96-107页

作者： Mengyu Hong Xiankun zhang Yu Geng Yunan Wang Xiaofu wei Li Gao Huihui Yu zhihong Cao zheng zhang Yue zhang Academy for Advanced Interdisciplinary Science and Technology School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijingthe People's Republic of China Key Laboratory of Advanced Materials and Devices for Post-Moore Chips Ministry of EducationUniversity of Science and Technology BeijingBeijingthe People's Republic of China

Metal–semiconductor contacts are crucial components in semiconductor *** two-dimensional transition-metal dichalcogenide semiconductors can sustain transistor scaling for next-generation integrated ***,their performance is often degraded by conventional metal deposition,which results in a high barrier due to chemical disorder and Fermi-level pinning(FLP).Although,transferring electrodes can address these issues,they are limited in achieving universal transfer of full-class metals due to strong adhesion between pre-deposited metals and ***,we propose a nanobelt-assisted transfer strategy that can avoid the adhesion limitation and enables the universal transfer of over 20 different types of *** contacts obey the Schottky–Mott rule and exhibit a FLP of S=*** the electron and hole contacts show record-low Schottky barriers of 4.2 and 11.2 meV,*** a demonstration,we construct a doping-free WSe_(2) inverter with these high-performance contacts,which exhibits a static power consumption of only 58 *** strategy provides a universal method of electrode preparation for building high-performance post-Moore electronic devices.

关键词： metal electrode transfer metal–semiconductor contacts Schottky barrier two-dimensional semiconductors

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

Insertion sequence transposition activates antimycobacteriophage immunity through an Isr2-silenced lipid metabolism gene island

引用

mLife 2024年第1期3卷 87-100页

作者： Yakun Li Yuyun wei Xiao Guo Xiaohui Li Lining Lu Lihua Hu zheng-Guo He State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangxi Research Center for Microbial and Enzyme Engineering TechnologyCollege of Life Scienceand TechnologyGuangxi UniversityNanningChina

Insertion sequences(ISs)exist widely in bacterial genomes,but their roles in the evolution of bacterial antiphage defense remain to be ***,we report that,under the pressure of phage infection,the IS1o96 transposition of Mycobacterium smegmatis into the Isr2 gene can occur at high frequencies,which endows the mutant mycobacterium with a broad-spectrum antiphage ***2 functions as a negative regulator and directly silences expression of a gene island composed of 11 lipid metabolism-related *** complete or partial loss of the gene island leads to a significant decrease of bacteriophage adsorption to the mycobacterium,thus defending against phage ***,a phage that has evolved mutations in two tail-filament genes can re-escape from the Isr2 inactivation-triggered host *** study uncovered a new signaling pathway for activating antimycobacteriophage immunity by Is transposition and provided insight into the natural evolution of bacterial antiphage defense.

关键词： antiphage defense bacteriophage gene island insertion sequence mycobacteria

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

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：