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华东、华南和西南地区烟粉虱的种群及寄主分化(英文)

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昆虫学报 2009年第10期52卷 1132-1138页

作者： Muhammad z.ahmed 沈媛金桂华任顺祥杜予州邱宝利华南农业大学资环学院昆虫学系广州510640 扬州大学园艺与植物保护学院江苏扬州225009

烟粉虱Bemisia tabaci是一个复合种,它具有的生物型分化、较强的传播病毒的能力和抗药性、较快的繁殖速率等特征使其成为我国农业生产中重要害虫之一。本研究利用细胞色素线粒体氧化酶Ⅰ基因,对采集自江苏、广东和云南三省的烟粉虱样本... 详细信息

烟粉虱Bemisia tabaci是一个复合种,它具有的生物型分化、较强的传播病毒的能力和抗药性、较快的繁殖速率等特征使其成为我国农业生产中重要害虫之一。本研究利用细胞色素线粒体氧化酶Ⅰ基因,对采集自江苏、广东和云南三省的烟粉虱样本进行了生物型鉴定,并对烟粉虱生物型与寄主植物之间的关联性开展了调查。结果表明,在广东和云南省,都存在未鉴定的土著种群与入侵的B型、Q型共存的现象;同时,在本研究中广东省尚未采集到Q型烟粉虱,而在江苏采集到的粉虱样本全部为入侵型。研究结果还表明,相对于入侵种而言,土著种群显示出更强的寄主植物趋同性;丰富的寄主植物以及本身具有的多食性特性有助于B型、Q型等生物型在世界各地的广泛入侵。

关键词：烟粉虱生物型寄主植物地理分布中国

One-pot Synthesis,Crystal Structures and Antimicrobial Activities of Two New 1,4-Disubstituted 1,2,3-Triaz.le-4-Carboxylates

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Chinese Journal of Structural Chemistry 2015年第1期34卷 26-32页

作者： MUHAMMAD Naeem ahmed KHAWAJA Ansar Yasin MUHAMMAD Nawaz.Tahir IFz.N Arshad MURTAz. Madni Department of Chemistry The University of Azad Jammu and Kashmir University of Sargodha Department of Physics Department of Chemistry Quaid-i-Azam University

Two new 1,4-disubstituted 1,2,3-triaz.les-4-carboxylates were synthesiz.d via click reaction. Compound 1a was synthesiz.d by the interaction of 6-nitro-tetraz.lo[1.5-a]-pyridine with ethyl propynoate at room temperature in the presence of Cu（OAc）2 as a catalyst and THF as solvent. Compound 1b was also synthesiz.d by the same manner except that tert-butyl propionate, instead of ethyl propynoate, was used. The compounds were characteriz.d by IR, 1H-NMR, 13C-NMR and single-crystal X-ray diffraction analysis. Compound 1a（C10H9N5O4） crystalliz.s in the triclinic system, space group P1 with a = 5.0894（9）, b = 8.9834（13）, c = 13.089（2）？, α= 83.041（7）, β= 80.256（7）, γ=87.296（8）°, V = 585.24（16）？3, z.= 2, Mr = 263.22, crystal siz.（mm） = 0.37 × 0.20 ×0.18,（I 〉 2σ（I）） = 8557, 2493, 1229, Rint = 0.057. Compound 1b（C12H13N5O4） crystalliz.s in the monoclinic system, space group P21/c with a = 6.8854（5）, b = 21.783（2）, c = 9.3986（8）？,β = 93.239（4）°, V = 1407.4（2）？3, z.= 4, Mr = 291.27, crystal siz.（mm） = 0.38 × 0.22 × 0.20,（I 〉 2σ（I）） = 11842, 3172, 1866, Rint = 0.047. Antimicrobial assay results showed that the title compounds display excellent activities to different bacterial and fungal strains.

关键词： click reaction triaz.les crystal structure antimicrobial activity

A Novel Cryptocurrency Prediction Method Using Optimum CNN

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Computers, Materials & Continua 2022年第4期71卷 1051-1063页

作者： Syed H.Hasan Syeda Huyam Hasan Mohammed Salih ahmed Syed Hamid Hasan Iowa State University AmesUSA University of Texas at Arlington USA Department of Computer Engineering College of Computer Science and Information TechnologyImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddahSaudi Arabia

In recent years,cryptocurrency has become gradually more significant in economic regions *** cryptocurrencies,records are stored using a cryptographic *** main aim of this research was to develop an optimal solution for predicting the price of cryptocurrencies based on user opinions from social *** is used as a marketing tool for cryptoanalysis owing to the unrestricted conversations on cryptocurrencies that take place on social media ***,this work focuses on extracting Tweets and gathering data from different sources to classify them into positive,negative,and neutral categories,and further examining the correlations between cryptocurrency movements and Tweet *** paper proposes an optimiz.d method using a deep learning algorithm and convolution neural network for cryptocurrency prediction;this method is used to predict the prices of four cryptocurrencies,namely,Litecoin,Monero,Bitcoin,and *** results of analyses demonstrate that the proposed method forecasts prices with a high accuracy of about 98.75%.The method is validated by comparison with existing methods using visualiz.tion tools.

关键词： Cryptocurrency litecoin monero bitcoin ethereum twitter optimal CNN price prediction sentiment analysis

Corrosion behavior of cold-rolled and post heat-treated 316L stainless steel in 0.9wt%NaCl solution

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 440-449页

作者： K.Bin Tayyab A.Farooq A.ahmed Alvi A.Basit Nadeem K.M.Deen Corrosion Control Research Cell Department of Metallurgy and Materials EngineeringUniversity of the PunjabLahorePakistan Department of Materials Engineering The University of British ColumbiaVancouverV6T 1Z4BCCanada

The effect of cold rolling and post-rolling heat treatment on the microstructural and electrochemical properties of the 316L stainless steel was ***-pass and four-pass cold-rolled stainless steel specimens were heat-treated by annealing at 900℃followed by quenching in *** the cold rolling,the microstructure of the as-received specimen transformed from austenite to strain-inducedα′-martensite due to significant plastic deformation that also resulted in significant grain elongation(i.e.,~33%and 223%increases in the grain elongation after two and four rolling passes,respectively).The hardness of the heat-treated as-received specimen decreased from HV 190 to 146 due to the recovery and recrystalliz.tion of the austenite grain *** cyclic polariz.tion scans of the as-rolled and heat-treated specimens were obtained in 0.9wt%NaCl *** pitting potential of the four-pass rolled specimen was significantly increased from 322.3 to 930.5 mV after post-rolling heat *** beneficial effect of the heat treatment process was evident from~10-times-lower corrosion current density and two-orders-of-magnitude-lower passive current density of the heat-treated specimens compared with those of the as-rolled ***,appreciably lower corrosion rate(3.302×10^(−4)mm/a)and higher pitting resistance(1115.5 mV)were exhibited by the postrolled heat-treated specimens compared with the as-rolled 316L stainless steel specimens.

关键词： cold rolling quenching cyclic polariz.tion re-passivation tendency

中国寄生烟粉虱的三种恩角蚜小蜂28S rRNA系统发育分析(英文)

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昆虫学报 2012年第2期55卷 189-198页

作者：薛夏彭伟录 Muhammad z.ahmed Nasser S.MANDOUR 任顺祥 Andrew G.S.CUTHBERTSON 邱宝利华南农业大学昆虫学系教育部生物防治工程中心 Department of Plant Protection Suez.Canal University The Food and Environment Research Agency Sand Hutton York YO41 1Lz UK

蚜小蜂Bemisia tabaci是烟粉虱的重要天敌,其中双斑恩蚜小蜂Encarsia bimaculata,丽蚜小蜂***以及浅黄恩蚜小蜂***是国内烟粉虱寄生蜂3个优势种。本研究以采自中国华南、华东、华北、西南地区以及马来西亚、埃及的***、***和***3个优势... 详细信息

蚜小蜂Bemisia tabaci是烟粉虱的重要天敌,其中双斑恩蚜小蜂Encarsia bimaculata,丽蚜小蜂***以及浅黄恩蚜小蜂***是国内烟粉虱寄生蜂3个优势种。本研究以采自中国华南、华东、华北、西南地区以及马来西亚、埃及的***、***和***3个优势种的8个不同地理种群为研究对象,对其28S rRNA D2和D3扩展区序列进行了测定和分析。结果表明:Encarsia属的恩蚜小蜂其28S rRNA D2和D3序列在种间水平上高度保守;与丽蚜小蜂相比,双斑蚜小蜂与浅黄恩蚜小蜂在遗传关系上更为接近。依据28S rRNA和D2序列的系统发育分析结果显示,同一种的蚜小蜂其种内也存在一定的遗传分化,比如中国广东的浅黄恩蚜小蜂种群与澳大利亚、西班牙、埃及和埃塞俄比亚的浅黄恩蚜小蜂种群接近,而与泰国的种群的亲缘关系则较远。在系统发育树上,来自不同国家的(苏丹、埃及和危地马拉以及澳大利亚)的双斑蚜小蜂种群聚集在同一分支上;同时,来自中国衡水和昆明的丽蚜小蜂种群也与来自美国的丽蚜小蜂种群聚集在一起,却与埃及的种群相距较远。对造成这种同种寄生蜂不同种群之间在遗传距离和地理距离不对称的原因进行了探讨。

关键词：蚜小蜂科恩角蚜小蜂 28SrRNA 遗传距离系统发育烟粉虱

Inhomogeneous-strain-induced magnetic vortex cluster in one-dimensional manganite wire

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Science Bulletin 2020年第3期65卷 201-207页

作者： Iftikhar ahmed Malik Houbing Huang Yu Wang Xueyun Wang Cui Xiao Yuanwei Sun Riz.an Ullah Yuelin z.ang Jing Wang Muhammad Abdullah Malik Irfan ahmed Changmin Xiong Simone Finiz.o Mathias Kl?ui Peng Gao Jie Wang Jinxing z.ang Department of Physics Beijing Normal UniversityBeijing 100875China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Department of Engineering Mechanics&Key Laboratory of Soft Machines and Smart Devices of z.ejiang Province Zhejiang UniversityHangzhou 310027China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Department of Physics University of Science and Technology BeijingBeijing 100083China International Center for Quantum Materials and Electron Microscopy Laboratory School of PhysicsPeking UniversityBeijing 100871China Department of Physics Johannes Gutenberg-University MainzMainz 55099Germany Graduate School of Excellence Materials Science in Mainz Mainz 55128Germany Collaborative Innovation Center of Quantum Matter Beijing 100871China

Mixed-valance manganites with strong electron correlation exhibit strong potential for spintronics,where emergent magnetic behaviors,such as propagation of high-frequency spin waves and giant topological Hall Effects can be driven by their mesoscale spin ***,we create magnetic vortex clusters with flux closure spin configurations in single-crystal La0.67Sr0.33MnO3 wire.A distinctive transformation from out-of-plane domains to a vortex state is directly visualiz.d using magnetic force microscopy at 4 K in wires when the width is below 1.0μ*** phase-field modeling indicates that the inhomogeneous strain,accompanying with shape anisotropy,plays a key role for stabiliz.ng the flux-closure spin *** work offers a new perspective for understanding and manipulating the non-trivial spin textures in strongly correlated systems.

关键词： Magnetic vortex cluster Inhomogeneous strain One-dimensional manganites Epitaxial thin films Cryo-Temperature MFM

Magnetic field induction and magnetic force distribution profiles in plasma focus discharge device

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Plasma Science and Technology 2021年第7期23卷 110-120页

作者： A A LASHIN T M ALLAM H A EL-SAYED Kamal M ahmed S A WARD H M SOLIMANand M A ABOUELATTA Plasma and Nuclear Fusion Department Nuclear Research CentreEgyptian Atomic Energy AuthorityInshas 13759Egypt Faculty of Engineering Delta University for Science and TechnologyGamasa 11152Egypt Electrical Engineering Department Faculty of Engineering at ShoubraBenha UniversityCairo 11629Egypt

We report a simple-to-perform technique to investigate the distribution of the az.muthal magnetic field induction,Bθ,and the induced magnetic force acting on the plasma current sheath(PCS)in a plasma focus(PF)*** in situ measurement technique can undoubtedly be beneficial when other fast-imaging techniques are not *** are not *** work was conducted in the low-energy Mather-type EAEA-PF1 device operated in *** axial distribution(Bθ)z.along the coaxial electrodes system was measured with a four magnetic-probe set technique at different radial distances(r=2.625×10^(−2) to 4.125×10^(−2) m)within the annular space between the coaxial electrodes during the 1st and 2nd half cycles of the discharge current waveform,where inner electrode of coaxial electrode system has a+ve polarity and−ve polarity,***,radial and total magnetic force distribution profiles were estimated from Bθ*** of PCS shape in terms of its inclination(curvature)angle,θ,along the axial rundown phase and the correlation between the magnetic forces per unit volume acting on the PCS,the inclination angleθof the PCS,and the formation of a powerful PF action during the 1st and 2nd half cycles is carried *** of inclination angle,θ,on total magnetic force per unit volume acting on PCS axial motion was studied,separately,during the 1st and 2nd half cycles.

关键词： plasma focus az.muthal magnetic field magnetic force inclination angle plasma current sheath

Phylogenetic Analysis of Bemisia tabaci (Hemipotera:Aleyrodidae) Populations from Cotton Plants in Pakistan,China and Egypt

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Phylogenetic Analysis of Bemisia tabaci (Hemipotera:Aleyrodi...

Multiscale simulations of growth-dominated Sb2Te phase-change material for non-volatile photonic applications

The 5th International Bemisia Workshop

作者： Muhammad z.ahmed Nasser S.Mandour M.N.Maruthi Muhammad Naveed Department of Entomology South China Agricultural University Department of Plant Protection Suez Canal UniversityIsmailia41522Egypt Plant Animal and Human Health GroupNatural Resources InstituteUniversity of GreenwichChatham MaritimeKentUnited Kingdom

Bemisia tabaci is a species complex,of which the B and Q biotypes are globally *** feeds on more than 600 plant species including cotton,which is one of the main crops in *** our study,the biotypes/haplotypes of *** populations collected from cotton plants in Pakistan,China,and Egypt were identified,and their phylogenetic relationships were *** of the populations from Pakistan or Egypt belonged to the B or Q biotype:all 16 samples from Pakistan belonged to haplotype "PCG-1" and it is a group of unresolved populations all from Pakistan,while all three populations from

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npj Computational Materials 2023年第1期9卷 928-936页

作者： Xu-Dong Wang Wen z.ou Hangming z.ang Shehz.d ahmed Tiankuo Huang Riccardo Maz.arello En Ma Wei z.ang Center for Alloy Innovation and Design(CAID) State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710049China Department of Physics Sapienza University of RomeRome 00185Italy

Chalcogenide phase-change materials(PCMs)are widely applied in electronic and photonic applications,such as non-volatile memory and neuro-inspired *** Sb2Te alloys are now gaining increasing attention for on-chip photonic applications,due to their growth-driven crystalliz.tion ***,it remains unknown whether Sb2Te also forms a metastable crystalline phase upon nanoseconds crystalliz.tion in devices,similar to the case of nucleation-driven Ge-Sb-Te ***,we carry out ab initio simulations to understand the changes in optical properties of amorphous Sb2Te upon crystalliz.tion and post *** the continuous transformation process,changes in the dielectric function are highly wavelength-dependent from the visible-light range towards the telecommunication *** finite-difference time-domain simulations based on the ab initio input reveal key differences in device output for color display and photonic memory applications upon tellurium *** work serves as an example of how multiscale simulations of materials can guide practical photonic phase-change applications.

关键词： transformation crystalliz.tion phase