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

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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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

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Heuristic multistep attack scenarios construction based on kill chain

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The Journal of China Universities of Posts and Telecommunications 2023年第5期30卷 61-71页

作者： Cheng Jie Zhang Ru Wei Jiahui lu Chen lü Zhishuai lin Bingjie Xia ang State Grid Information and Telecommunication Branch Beijing 100761China School of Cyberspace Security Beijing University of Posts and TelecommunicationsBeijing 100876China

Network attacks evolved from single-step and simple attacks to complex multistep *** methods of multistep attack detection usually match multistep attacks from intrusion detection systems(IDS)alarms based on the correlation between attack ***,IDS has false negatives and false positives,which leads to incomplete or incorrect multistep *** based on simple similarity is difficult to obtain an accurate attack cluster,while association based on prior knowledge such as attack graphs is difficult to guarantee a complete attack knowledge *** solve the above problems,a heuristic multistep attack scenarios construction method based on the kill chain(HMASCkC)model was *** attack model graph can be obtained from dual data sources and heuristic multistep attack scenarios can be obtained through graph *** model graph of the attack and the predicted value of the next attack are obtained by calculating the matching *** according to the purpose of the multistep attack,the kill chain model is used to define the initial multistep attack model,which is used as the initial graph for graph *** results show that HMASCkC model can better fit the multistep attack behavior,the effect has some advantages over the longest common subsequence(lCS)algorithm,which can close to or match the prediction error of judge evaluation of attack intension(JEAN)*** method can make multistep attack model matching for unknown attacks,so it has some advantages in practical application.

关键词： multistep attack scenario kill chain graph matching attack prediction

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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

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Understanding yields in alley cropping maize (Zea mays l.) and Cassia siamea lam. under semi-arid conditions in Machakos, Eastern kenya

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Journal of Environmental Sciences 2001年第3期13卷 291-298页

作者： DNMungai CJStigter ClCoulson JkNg’ang’A GWSNetondo GOUmaya TTMI Project University of NairobiP.O.Box 30197NairobiKenya Department of Geography Department of Botany Department of Meteorology TTMI-Project Department of Environmental SciencesCT.de Wit Graduate School of Production Ecology and Resource ConservationWageningen UniversityDuivendaal 26701 AP WageningenThe Netherlands.

Six seasons of experiments in Machakos, kenya, revealed that above about 150 mm of rainfall, maize yields per row in alley cropped “replacement” agroforestry (AF) plots, of Cassia siamea lam. and maize ( Zea mays, cv. katumani Composite B), may be expected to exceed those in the control (sole maize) plots. Such yields were insufficient to compensate for the area “lost” to the hedgerows. Below about 150 mm the control plots may be expected to perform better. This result was due to competition for water. Greater association of the fine roots of Cassia and maize was observed in the middle of the alleys than near the hedgerows. Photosynthetic consequences of shading were insignificant relative to other factors. In the alleys, reductions of soil temperature due to shade in the western and eastern maize rows were higher than in the middle row. Soil moisture extraction was higher in the AF than in the control plots. In the AF plots, moisture extraction was greater under the central maize rows than under those nearest the Cassia. Yield patterns followed such soil temperature and soil moisture patterns. Maize transpiration and photosynthetic rates were significantly higher in the control than in the AF plots during a below average rainy season but not during above average rainy seasons. It is concluded that alley cropping under semi arid conditions should be approached differently from the system worked on. It must at least provide strong physical protection of crops and/or soils and have a strong economic incentive to be of interest to the farmers.

关键词： alley cropping Cassia siamea competition kenya maize yields microclimate mulching semi arid conditions

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Arabidopsis Profilin Isoforms,PRF1 and PRF2 Show Distinctive Binding Activities and Subcellular Distributions

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Journal of Integrative Plant Biology 2009年第2期51卷 113-121页

作者： Feng ang Yanping Jing Zhen ang Tonglin Mao Jozef Samaj Ming Yuan Haiyun Ren State key laboratory of Plant Physiology and Biochemistry China Agricultural University Beijing 100094 China College of life Sciences Beijing Normal University Beijing 100875 China College of Biological Sciences and Biotechnology Beijing Forestry University Beijing 100083 China Institute of Cellular and Molecular Botany Rheinische Friedrich-Wilhelms- University Bonn Department of Plant Cell Biology Kirschallee 1 D-53115 Bonn Germany Institute of Plant Genetics and Biotechnology Slovak Academy of Sciences Akademicka 2 SK-95007 Nitra Slovak Republic

Profilin is an actin-binding protein that shows complex effects on the dynamics of the actin cytoskeleton. There are five profilin isoforms in Arabidopsis thaliana l. However, it is still an open question whether these isoforms are functionally different. In the present study, two profilin isoforms from Arabidopsis, PRF1 and PRF2 were fused with green fuorescent protein （GFP） tag and expressed in Escherichia coil and A. thaliana in order to compare their biochemical properties in vitro and their cellular distributions in vivo. Biochemical analysis revealed that fusion proteins of GFP-PRF1 and GFP-PRF2 can bind to poly-l-proline and G-actin showing remarkable differences. GFP-PRF1 has much higher affinities for both poly-l-proline and G-actin compared with GFP-PRF2. Observations of living cells in stable transgenic A. thaliana lines revealed that 35S：：GFP-PRF1 formed a filamentous network, while 35S：：GFP-PRF2 formed polygonal meshes. Results from the treatment with latrunculin A and a subsequent recovery experiment indicated that filamentous alignment of GFP-PRF1 was likely associated with actin filaments. However, GFP-PRF2 localized to polygonal meshes resembling the endoplasmic reticulum. Our results provide evidence that Arabidopsis profllin isoforms PRF1 and PRF2 have different biochemical affinities for poly-l-proline and G-actin, and show distinctive Iocalizations in living cells. These data suggest that PRF1 and PRF2 are functionally different isoforms.

关键词： actin filaments Arabidopsis endoplasmic reticulum profilin isoforms PRF1 PRF2

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Assessment of Pb uptake,translocation and immobilization in kenaf (Hibiscus cannabinus l.) for phytoremediation of sand tailings

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Journal of Environmental Sciences 2008年第11期20卷 1341-1347页

作者： HO Wai Mun ang lai Hoe lEE Don koo Forest Research Institute Malaysia 52109 KepongSelangorMalaysia Department of Forest Sciences Seoul National UniversitySeoul 151-921Korea

The potential of kenaf (Hibiscus cannabinus l.) for phytoremediation of lead (Pb) on sand tailings was investigated.A pot experiment employing factorial design with two main effects of fertilizer and lead was conducted in a nursery using sand tailings from an ex-tin mine as the growing *** showed that Pb was found in the root,stem,and seed capsule of kenaf but not in the *** of organic fertilizer promoted greater biomass yield as well as higher accumulation capacity of *** Pb-spike...

关键词： kenaf lead fertilizer bioaccumulation capacity phytoremediation

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Effect of Vane Opening on Aerodynamic Performance of the Ram-rotor Test System

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Journal of Thermal Science 2016年第3期25卷 207-215页

作者： HAN Ji-ang GUAN Jian ZHONG Jingjun YUAN Chenguang Marine Engineering College Dalian Maritime University

In order to research the influence of adjustable vane on the aerodynamic performance of the ram-rotor test system, FlUENT soft-ware has been adopted to simulate the flow passage of the ram-rotor test system numerically. The vane opening is controlled by changing the stagger angle of the vane blades. Results show that flow uniformity of vane outlet is influenced by the vane openings, which has an impact on the aerodynamic loss to some extent. Total pressure ratio, adiabatic efficiency and mass flow rate can be regulated by different openings of the vane. Compared with -8° vane opening, top efficiency of the ram-rotor increases by about 13.8% at ＋6° opening. And total pressure ratio drops by 5.87%. The rising opening increases the relative Mach number at inlet of the ram-rotor and weakens the intensity of the tip clearance leakage, which comes to a decreasing aerodynamic loss.

关键词： adjustable vane ram-rotor test system aerodynamic performance numerical simulation

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A Nonclassical lIl for Geometrically Weighted Series in Banach Space

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Acta Mathematica Sinica,English Series 2013年第7期29卷 1413-1420页

作者： ke ang FU Xiao Rong Yang Wei HUang School of Statistics and Mathematics Zhejiang Gongshang University Department of Mathematics Zhejiang University

We consider efficient methods for the recovery of block sparse signals from underdetermined system of linear equations. We show that if the measurement matrix satisfies the block RIP with δ2s 〈 0.4931, then every block s-sparse signal can be recovered through the proposed mixed l2/ll-minimization approach in the noiseless case and is stably recovered in the presence of noise and mismodeling error. This improves the result of Eldar and Mishali （in IEEE Trans. Inform. Theory 55： 5302-5316, 2009）. We also give another sufficient condition on block RIP for such recovery method： 58 〈 0.307.

关键词： Banach space geometrically weighted series nonclassical law of the iterated logarithm

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Primary hepatic myelolipoma: A case report and review of the literature

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World Journal of Clinical Cases 2020年第19期8卷 4615-4623页

作者： ke-Yu li Ai-lin Wei ang li Department of Hepato-Bilio-Pancreatic Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACkGROUND Primary hepatic myelolipoma is a rare hepatic mesenchymal tumor mixed by adipose tissue and bone marrow,and there is a lack of general guidelines related to its epidemiology and clinical *** SUMMARY A 26-year-old woman was admitted to our department complaining of a newly found tumor on her left lobe of the *** tumor was painless and not associated with any systemic or localized compressive *** tests disclosed a slight increase of gamma-glutamyl transpeptidase(70.0 U/l)and total bilirubin(19.2 pmol/l).Ultrasonography showed a mass about 5.0 cm x 5.0 cm in size that was located in the left lobe of the liver and displayed hyperechoic and well-encapsulated *** resection was applied,and the following histopathological examination observed a variable proportion of myeloid tissues scattering throughout mature fibrotic adipose tissues,in which myeloid,erythroid,and megakaryocytic cells can be found in magnified *** follow-up did not show any changes 6 mo after *** This case highlights an extremely rare hepatic mesenchymal tumor,the primary hepatic myelolipoma,and discloses the common characteristics behind this disease and gives clinical recommendations.

关键词： Hepatic myelolipoma liver neoplasms Myelolipoma Tumor liver Extraadrenal myelolipoma Case report

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