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Broadband strong optical dichroism in topological Dirac semimetals with Fermi velocity anisotropy

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Chinese Physics B 2020年第7期29卷 128-134页

作者： j Lim K j A Ooi C Zhang L K ang Yee Sin ang Science Math and TechnologySingapore University of Technology and DesignSingapore School of Energy and Chemical Engineering Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China School of Physics University of WollongongNorthfields AvenueNew South Wales 2522Australia

Prototypical three-dimensional(3D)topological Dirac semimetals(DSMs),such as Cd3As2 and Na3Bi,contain electrons that obey a linear momentum-energy dispersion with different Fermi velocities along the three orthogonal momentum *** being extensively studied in recent years,the inherent Fermi velocity anisotropy has often been neglected in the theoretical and numerical studies of 3D *** this omission does not qualitatively alter the physics of light-driven massless quasiparticles in 3D DSMs,it does quantitatively change the optical coefficients which can lead to nontrivial implications in terms of nanophotonics and plasmonics *** we study the linear optical response of 3D DSMs for general Fermi velocity values along each *** the signature conductivity-frequency scaling,σ(ω)∝ω,of 3D Dirac fermion is well-protected from the Fermi velocity anisotropy,the linear optical response exhibits strong linear dichroism as captured by the universal extinction ratio scaling law,Λi j=(vi/v j)^2(where i=j denotes the three spatial coordinates x,y,z,and vi is the i-direction Fermi velocity),which is independent of frequency,temperature,doping,and carrier scattering *** Cd3As2 and Na3Bi3,an exceptionally strong extinction ratio larger than 15 and covering a broad terahertz window is *** findings shed new light on the role of Fermi velocity anisotropy in the optical response of Dirac semimetals and open up novel polarization-sensitive functionalities,such as photodetection and light modulation.

关键词： topological Dirac semimetal optical anisotropy linear dichroismn linear response theory

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涡轮叶片吸力面双排分区复合角气膜冷却特性

工程热物理学报 2024年第3期45卷 792-802页

作者：王晨枫李国庆刘浩李昂张燕峰卢新根江苏大学流体机械工程技术研究中心镇江212013 中国科学院工程热物理研究所北京100190 中国科学院大学航空宇航学院北京100190 轻型涡轮动力全国重点实验室北京100190

通道二次流作用下,涡轮叶片吸力面气膜轨迹呈收缩状从叶片两端朝叶中偏转。针对该问题,本文设计了高压涡轮叶片吸力面双排分区域复合角气膜冷却模型,并采用数值模拟的方法,分析了二次流和复合角对气膜冷却特性的影响。结果表明,在近端区... 详细信息

通道二次流作用下,涡轮叶片吸力面气膜轨迹呈收缩状从叶片两端朝叶中偏转。针对该问题,本文设计了高压涡轮叶片吸力面双排分区域复合角气膜冷却模型,并采用数值模拟的方法,分析了二次流和复合角对气膜冷却特性的影响。结果表明,在近端区,叶片上游孔排SS1形成的气膜受马蹄涡的作用偏转较小,叶片下游孔排SS2形成的气膜受较强通道涡的影响偏转角远大于上游气膜;在叶片吸力面增加朝向端壁的复合角设计,可以改善气膜覆盖的均匀性,复合角增大至30?左右时,可以消除射流的脱壁现象,最大复合角工况相比于简单角工况的展向平均气膜冷却效率提高了13.9%。

关键词：涡轮导叶气膜冷却通道二次流分区域复合角冷却效率

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人工智能在废水处理领域研究的发展态势分析

安全与环境学报 2024年第5期24卷 1985-1996页

作者：王田力陈伊宁李昂孙宝平首都经济贸易大学财政税务学院北京100070 首都经济贸易大学安全工程系北京100070

为深入了解人工智能技术在废水处理领域应用研究的发展态势,对1990—2023年Web of Science数据库中990篇人工智能与废水处理交叉领域文献进行了计量分析。研究结果显示,本地引用次数(Total Local Citation Score,TCLS)排名前4的期刊分别... 详细信息

为深入了解人工智能技术在废水处理领域应用研究的发展态势,对1990—2023年Web of Science数据库中990篇人工智能与废水处理交叉领域文献进行了计量分析。研究结果显示,本地引用次数(Total Local Citation Score,TCLS)排名前4的期刊分别是Process Safety and Environmental Protection、Engineering Applications of Artificial Intelligence、Water Science and Technology和journal of Environmental Sciences;本地引用次数(Total Local Citation Score,TLCS)排名前10的期刊中有6个期刊来自于英国,其他期刊分别来自于中国、意大利、德国和美国。中国学者在该领域的发文量、TLCS全球排名第一,全球引用次数(Total Global Citation Score,TGCS)全球排名第一,体现了中国学者对人工智能与废水处理交叉领域的关注度较高。在发文量排名前10的机构中有4所来自中国,分别是北京工业大学、中国科学院、哈尔滨工业大学和清华大学,合计的发文量占前10总数的25.1%。有4名中国学者进入了发文量前10,分别为北京工业大学的Qiao j F、Wang D、Han H G以及哈尔滨工业大学的Ren N Q。通过关键词分析发现,人工神经网络是本领域的研究热点之一,利用神经网络来预测废水处理的效果是当前的热点话题。

关键词：环境工程学废水处理人工智能

腹腔镜小儿肾盂成形术中不同手术入路选择的临床研究

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现代泌尿生殖肿瘤杂志 2024年第2期16卷 81-84页

作者：唐亚斯禹伸频叶春伟李志鹏昆明医科大学第一附属医院昆明650032 昆明医科大学第三附属医院昆明医科大学第二附属医院

目的比较经腹腔入路和经腹膜后入路行腹腔镜小儿肾盂成形术的临床疗效。方法收集2018年1月至2022年12月14岁及以下行腹腔镜肾盂成形术的123例患儿,其中经腹腔入路58例,经腹膜后入路65例,比较两组的术中、术后指标以及术后并发症。结果... 详细信息

目的比较经腹腔入路和经腹膜后入路行腹腔镜小儿肾盂成形术的临床疗效。方法收集2018年1月至2022年12月14岁及以下行腹腔镜肾盂成形术的123例患儿,其中经腹腔入路58例,经腹膜后入路65例,比较两组的术中、术后指标以及术后并发症。结果经腹腔入路组的年龄小于经腹膜后入路组(P0.05)。结论年龄较大的患儿可选择经腹膜后入路,低位肾盂输尿管连接处梗阻、年龄小的小儿,尤其婴幼儿,推荐经腹腔入路,两种入路均有各自优势,应根据患儿发育、年龄和解剖结构特点来选择手术入路,可以降低手术难度,减少并发症,提高手术精细度和成功率。

关键词：小儿腹腔镜肾盂输尿管连接处梗阻肾盂成形术手术入路

A Numerical Study Comparing the Effect on Residual Stresses of Two Different Types of Projectiles During Shot Peening

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Computers, Materials & Continua 2016年第3期51卷 203-215页

作者： j.Solórzano-López F.A.García-Pastor angélica Flores-Luna UNAM Facultad de QuímicaCiudad de MéxicoMéxico Cinvestav Unidad Saltillo CoahuilaMéxico TecNM Instituto Tecnológico de Tláhuac IIICiudad de MéxicoMéxico

Shot peening is a widely used technique to improve fatigue life in metallic *** processing technique introduces a subsurface compressive residual stress field through a plastic deformation of the surface caused by the impact of a large number of high-speed *** are a number of parameters that affect the residual stress field depth and *** effects of the impact angle,shot speed and shot geometry are currently being *** particular,substituting spherical cast shots by cylindrical cut wire shots is an attractive option,especially in terms of *** effect of shot geometry on residual stresses,however,needs to be further *** industrial-scale experimentation is costly and cumbersome,mathematical modeling offers a convenient alternative to carry out this type of *** present work shows a comparison between the residual stresses generated by the impact of spherical and cylindrical projectiles on a steel *** threedimensional model was developed using ABAQUS finite element commercial software(Release 6.12,Dassault Systémes,France).The results show that cylindrical shots generate residual stress fields t hat a re higher in magnitude than t hose generated by a spherical ***,the residual stress field of cylindrical shots impacting the surface at an oblique angle shows an important degree of *** effect is not found when spherical shots impact the surface at the same oblique angle.

关键词： Shot Peening Finite element method Residual Stresses

Phenotypic nutrient up-take differences in an alley cropping system in semi-arid Machakos, Kenya

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journal of Environmental Sciences 2001年第2期13卷 164-169页

作者： D.N. Mungai C.L.Coulson C.j. Stigter j.K. Ng’ang’a D.N.Mugendi Department of Geography University of NairobiNairdbiKenya Department of Botany University of NairobiNairobiKenya Department of Enviromnental Sciences Graduate School of Productian EcologyWageningen UniversityDuivendaal 26701 APThe Netherlands Department of Meteorology University of NairobiNairobiKenya Kenya Forestry Research Instiute(KEFRI NairobiKanya)

Alley cropping of Cassia siamea and maize was studied in semi arid Kenya for soil fertility improvement. Katumani composite maize was planted except in the short rains of 1988 (SR88) when a hybrid variety was sown. Therefore the grain yield per row increased differently in the alley cropped maize (CM). Sole maize (SM) and CM yields were higher in SR88 than in the long rains of 1988 (LR88) by 62% and 38%, while yields from the same treatments in LR89 were only 21% and 45% of those in SR88 These differences in relative maize yields are attributed to differences between the two maize varieties in competition under nutrient stress conditions.

关键词： alley cropping Cassia siamea maize nutrients maize yield semi arid condition soil moisture Kenya

Strange star candidates revised within a quark model with chiral mass scaling

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Research in Astronomy and Astrophysics 2011年第4期11卷 482-490页

作者： ang Li Guang-Xiong Peng ju-Fu Lu Department of Physics and Institute of Theoretical Physics and Astrophysics Xiamen University Xiamen 361005 China Department of Physics Graduate University Chinese Academy of Sciences Beijing 100049 China

We calculate the properties of static strange stars using a quark model with chiral mass scaling. The results are characterized by a large maximum mass （-1.6 M⊙） and radius （-10km）. Together with a broad collection of modern neutron star models, we discuss some recent astrophysical observational data that could shed new light on the possible presence of strange quark matter in compact stars. We conclude that none of the present astrophysical observations can prove or confute the existence of strange stars.

关键词： dense matter -- elementary particles -- equation of state -- stars: inte-riors

Immunohistochemical assessment of NY-ESO-1 expression in esophageal adenocarcinoma resection specimens

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World journal of Gastroenterology 2014年第14期20卷 4011-4016页

作者： Stephen j Hayes Keng Ngee Hng Peter Clark Fiona Thistlethwaite Robert E Hawkins Yeng ang Department of Histopathology Salford Royal NHS Foundation Trust Faculty of Medical and Human Sciences University of Manchester Department of Gastroenterology Salford Royal NHS Foundation Trust Department of Medical Oncology The Christie NHS Foundation Trust Department of Medical Oncology Paterson Institute of Cancer ResearchUniversity of Manchester

AIM: To assess NY-ESO-1 expression in a cohort of esophageal adenocarcinomas.

关键词： Esophageal adenocarcinoma Immunohistochemistry NY-ESO-1 Stem cells Vesicle trafficking

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多核堆栈处理器研究与设计

计算机工程与设计 2024年第4期45卷 1256-1263页

作者：刘自昂周永录代红兵刘宏杰云南大学信息学院云南昆明650500 云南大学云南省高校数字媒体技术重点实验室云南昆明650223

为满足日趋复杂的嵌入式环境对堆栈处理器和Forth技术的应用需求,在单核堆栈处理器模型研究的基础上,设计一种多核堆栈处理器模型。基于j1单核堆栈处理器模型,针对多核目标,增加计时器、中断等功能,形成新的L32单核堆栈处理器模型,并以... 详细信息

为满足日趋复杂的嵌入式环境对堆栈处理器和Forth技术的应用需求,在单核堆栈处理器模型研究的基础上,设计一种多核堆栈处理器模型。基于j1单核堆栈处理器模型,针对多核目标,增加计时器、中断等功能,形成新的L32单核堆栈处理器模型,并以该单核模型为内核,引入共享总线和十字开关互联方式的Wishbone总线、多端口存储器和面向多任务Forth系统的指令集,建立一种多核堆栈处理器模型L32-MC。利用该多核模型,在FPGA上实现4核和8核的L32-MC原型多核堆栈处理器。实验结果表明,4核和8核的L32-MC原型堆栈处理器满足高性能低功耗的多核处理器设计目标。

关键词：多核堆栈处理器 Forth技术 Wishbone片上总线多端口存储器指令集现场可编程门阵列嵌入式