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A novel diagnostic gene region for distinguishing between two pest fruit flies:Bactrocera tryoni(Froggatt)and Bactrocera neohumeralis(Hardy)(Diptera:Tephritidae)

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Insect Science 2024年第4期31卷 1285-1295页

作者： Melissa l.Starkie Elizabeth V.Fowler Alexander M.Piper Xiaocheng Zhu Pauline Wyatt David Gopurenko Matt N.Krosch Francesca Strutt Karen F.Armstrong Hamish Patrick Mark K.Schutze Mark J.Blacket Department of Agriculture and Fisheries BiosecurityBrisbaneQueenslandAustralia Agriculture Victoria AgriBioBundooraVictoriaAustralia Department of Primary Industries Wagga Wagga Agricultural InstituteWagga WaggaNew South WalesAustralia Forensic Services Group Queensland Police ServiceBrisbaneQueenslandAustralia Department of Pest-management and Conservation Lincoln UniversityLincolnNew Zealand Better Border Biosecurity(B3 B3nz.org.nz)LincolnNew Zealand

Bactrocera tryoni and Bactrocera neohumeralis are morphologically similar sibling pest fruit fly species that possess different biological attributes,geographic distributions,and host *** need to differentiate between the two species is critical for accurate pest status assessment,management,biosecurity,and maintenance of reference *** morphologically similar,adults may be separated based on subtle characters;however,some characters exhibit intraspecific variability,creating overlap between the two ***,there is currently no single molecular marker or rapid diagnostic assay that can reliably distinguish between *** and ***;therefore,ambiguous samples remain *** we report the first molecular marker that can consistently distinguish between *** and *** diagnostic region consists of two adjacent single nucleotide polymorphisms(SNPs)within the pangolin(pan)gene *** confirmed the genotypes of each species are consistent across their distributional range,then developed a tetra-primer amplification refractory mutation system(ARMS)PCR assay for rapid diagnosis of the *** assay utilizes four primers in multiplex,with two outer universal primers,and two internal primers:one designed to target two adjacent SNPs(AA)present in *** and the other targeting adjacent SNPs present in ***(GG).The assay accurately discriminates between the two species,but their SNP genotypes are shared with other nontarget tephritid fruit fly ***,this assay is most suited to adult diagnostics where species confirmation is necessary in determining ambiguous surveillance trap catches;maintaining pure colony lines;and in Sterile Insect Technique management responses.

关键词： ARMS-PCR colony molecular diagnostics pangolin tetra-primer

伺服机械压力机主传动机构多目标优化设计研究

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机械设计与研究 2024年第4期40卷 111-116页

作者：马敏海吕涛宁波职业技术学院精密模具加工及智能制造应用研究中心浙江宁波315800 宁波大学机械工程与力学学院浙江宁波315211

伺服机械压力机主传动机构决定了其工作性能的优劣,本文针对企业某型号伺服机械压力机曲柄三角肘杆机构的各项参数要求,提出了一种设计方法。首先,在通过运动学对曲柄三角肘杆机构进行解析环节中使用了复数矢量法;其次,根据设计变量和... 详细信息

伺服机械压力机主传动机构决定了其工作性能的优劣,本文针对企业某型号伺服机械压力机曲柄三角肘杆机构的各项参数要求,提出了一种设计方法。首先,在通过运动学对曲柄三角肘杆机构进行解析环节中使用了复数矢量法;其次,根据设计变量和约束条件在MATlAB(Matrix laboratory)中求解传动机构基础尺寸。然后,确定设计变量、约束条件及目标函数。最后,采用层次分析法(Analytic Hierarchy Process)确定线性加权和法的权重系数并通过惩罚函数法以及遗传算法的融合,对最终目标函数进行计算。通过研究证明,对比经常应用的权重系数来说,通过AHP法,对权重系数进行优化后,在公称压力行程中,曲柄三角肘杆机构的滑块速度降低了6.3%,行程速比系数提高了19.8%,传动机构的高度降低了1.3%。

关键词：伺服机械压力机多目标优化设计复数矢量法层次分析法遗传算法

Effect of static annealing on superplastic behavior of a friction stir welded Ti-6Al-4V alloy joint and microstructural evolution during deformation

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Journal of Materials Science & Technology 2022年第35期130卷 112-123页

作者： C.l.Jia l.H.Wu P.Xue D.R.Ni B.l.Xiao Z.Y.Ma Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Structural integration is one of the most critical developing directions in the modern aerospace field,in which large-scale complex components of Ti alloys are proposed to be fabricated via the method of welding + superplastic ***,the undesired strain localization appeared during superplastic deformation of the entire joint has largely hindered the development of this *** our study,a combination process of friction stir welding(FSW) + static annealing+ superplastic deformation was first time proposed to eliminate severe local *** achieve this result,a fully fine lamellar structure was obtained in the nugget zone(nz) via FSW,which was totally different from the mill-annealed structure in the base material(BM).After annealing at 900℃ for 180 min,the BM and nz then exhibited the similar elongation of> 500% and similar flow stress at 900 ℃,3 × 10^(-3)s^(-1),which was the precondition for achieving uniform superplastic deformation in the entire ***,the different microstructures in the BM and nz tended to become the similar equiaxed structure after deformation,which was the result of different microstructural evolution mechanisms in the nz and *** the nz,there was a static and dynamic spheroidization of the fully lamellar structure during the process,which could largely reduce the flow softening of the fully lamellar *** the BM,a new view of "langdon-CRSS theory"(CRSS,critical resolved shear stress) was proposed to describe the fragmentation of the coarse equiaxed structure,which established the relationship between grain boundary sliding and intragranular deformation during deformation.

关键词： Friction stir welding Titanium alloys Superplasticity Static annealing Microstructure

Static spheroidization and its effect on superplasticity of fine lamellae in nugget of a friction stir welded Ti-6Al-4V joint

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Journal of Materials Science & Technology 2022年第24期119卷 1-10页

作者： C.l.Jia l.H.Wu P.Xue H.Zhang D.R.Ni B.l.Xiao Z.Y.Ma Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The spheroidization of the lamellar structure can greatly contribute to the superplasticity of the nugget zone(nz)of Ti alloy welds,which is the key to achieve the integral superplastic forming of welds for the fabrication of large-scale complex ***,the spheroidization process is complex and costly since it cannot be obtained generally,unless the lamellae suffers from a large *** this study,the static spheroidization was achieved for the fine lamellae structure in the nugget of a friction stir welded(FSW)Ti-6Al-4V joint,particularly by the annealing without any *** specialα/βinterface obeying a Burgers orientation relationship(BOR)after FSW was first time directly observed,whose effect on the spheroidization was discussed.A new static spheroidization mechanism with the gradual coalescence of the adjacent lamellae was discovered,which we named as“termination coalescence”.There was a slower coarsening rate in the lamellar structure than in the classical equiaxed one,due to the BOR in the lamellae,although both of them exhibited a volume diffusion character during ***,the similar superplasticity can be achieved for the base material and nz after *** study can provide a new way to the spheroidization and a theoretical basis for the integral superplastic forming of welds during production.

关键词： Friction stir welding Titanium alloys Spheroidization mechanism Coalescence Superplasticity Static annealing

Porcine Coronaviruses: Overview of the State of the Art

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Virologica Sinica 2021年第5期36卷 833-851页

作者： Hanna Turlewicz-Podbielska Małgorzata Pomorska-Mo´l Department of Preclinical Sciences and Infectious Diseases Faculty of Veterinary Medicine and Animal SciencesPoznan University of Life Sciencesul.Wołyn´ska 3560-637 PoznanPoland

like RNA viruses in general,coronaviruses(CoV)exhibit high mutation rates which,in combination with their strong tendency to recombine,enable them to overcome the host species barrier and adapt to new *** is currently known that six CoV are able to infect *** of them belong to the genus Alphacoronavirus[transmissible gastroenteritis coronavirus(TEGV),porcine respiratory coronavirus(PRCV),porcine epidemic diarrhea virus(PEDV),swine acute diarrhea syndrome coronavirus(SADS-CoV)],one of them to the genus Betacoronavirus[porcine hemagglutinating encephalomyelitis virus(PHEV)]and the last one to the genus Deltacoronavirus(PDCoV).PHEV was one of the first identified swine CoV and is still widespread,causing subclinical infections in pigs in several ***,a spike deletion mutant of TGEV associated with respiratory tract infection,appeared in the 1980 *** is considered nonpathogenic since its infection course is mild or *** its appearance,pig populations have become immune to both PRCV and TGEV,leading to a significant reduction in the clinical and economic importance of ***,PEDV and PDCoV are enteropathogenic CoV and cause clinically indistinguishable acute gastroenteritis in all age groups of *** and SADS-CoV have emerged in 2014(US)and in 2017(China),*** diagnosis is crucial for controlling CoV infections and preventing them from *** vaccines are available only for some porcine CoV,prevention should focus mainly on a high level of *** view of the diversity of CoV and the potential risk factors associated with zoonotic emergence,updating the knowledge concerning this area is essential.

关键词： Coronavirus Pig Emerging Re-emerging

多分量地震技术在挪威中部边缘气体水合物调查的应用

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海洋地质 2008年第1期24卷 18-22页

作者： Stefan Bünz 徐华宁（译）张光学（校）

作为数量巨大的碳来源，天然气水合物可能是未来潜在的能源储备，也可能与全球的气候变化相关联，基于这一事实，在过去二十年中，天然气水合物方面的重要性持续上升是有目共睹的。此外，天然气水合物的分解以及并发的游离气释放造成潜... 详细信息

作为数量巨大的碳来源，天然气水合物可能是未来潜在的能源储备，也可能与全球的气候变化相关联，基于这一事实，在过去二十年中，天然气水合物方面的重要性持续上升是有目共睹的。此外，天然气水合物的分解以及并发的游离气释放造成潜在的海底坡身不稳。多分量地震技术能够拓宽对天然气水合物储层的认识。在海洋条件下，当下行传播的纵波（P波）在一个沉积界面反射时，可以转化而产生横波（S波）。利用水平和垂直的地震检波器可以在海底处记录到上行的S波。除P波数据外，S波数据非常有用，这是由于S波几乎不受多孔岩石中孔隙充填的影响并且速度较P波速度慢。这一性质清楚表明一个明显的优势，因为（1）利用S波可以提高地震分辨率；（2）含气或质量差的P波反射目标体可以较好成像；（3）孑l隙流体与岩性可以辨别；（4）增强估算气体水合物浓度的能力。在挪威中部边缘，多分量地震数据可使我们选择一个含水合物沉积物的可靠岩石物理模型。多分量地震数据能将气体或气体水合物对地震速度的影响与岩性对地震速度的影响进一步区分开。改进后的声成像结果使我们能清楚了解含水合物沉积层的下方区带，由于气体的存在，这一区带在P波数据上反射模糊。挪威中部边缘的天然气水合物研究很大程度上得益于对多分量数据的利用，部分数据由奥斯陆石油地质服务公司向特罗姆瑟大学地质系提供。

关键词：气体水合物地震技术多分量挪威天然气水合物含水合物沉积物应用 P波速度

Evidence of strong energetic ion acceleration in the near-Earth magnetotail

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Evidence of strong energetic ion acceleration in the near-Ea...

Effect of Y Addition on Microstructure and Mechanical Properties of Friction Stir Welded ZK60 Alloy

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： H.luo E.A.Kronberg E.E.Grigorenko M.Frnz P.W.Daly G.X.Chen A.M.Du l.M.Kistler Y.Wei Key laboratory of Ionospheric Environment Institute of Geology and GeophysicsChinese Academy of Sciences Max Planck Institute for Solar System Research Space Research Institute Russian Academy of Sciences Space Science Center University of New Hampshire

Until now it is still questionable whether ions are accelerated to energies above 100 keV in the near-Earth current sheet(CS),in the vicinity of a possible near-Earth neutral *** using 11 years of 3-D energetic ion flux data for protons,helium,and oxygen(50keV-1 MeV) from the RAPID instrument on board Cluster 4,we statistically study the energetic ion acceleration by investigating ion anisotropies in the near-Earth magnetotail(—20 fRlward) anisotropy of the energetic(>150 keV) ions(protons,He,and O) tend to become higher as the earthward(tailward) plasma bulk flows(measured by Cluster Ion Spectrometry experiment) become *** such periods the presence of a strong acceleration source tailward(earthward) of Cluster spacecraft(S/C) is confirmed by the hardening energy spectra of the earthward(tailward) energetic ion flows.A good statistical correlation between tailward bulk flow,negative Bz,and the tailward anisotropy of energetic ions indicates that the strong ion acceleration might be related to a near-Earth reconnection,which occurred earthward of the Cluster S/*** energetic ion anisotropies do not show a clear dependence on the AE index,which may indicate that the acceleration source(s) for the energetic ions could be spatially localized.

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Journal of Materials Science & Technology 2009年第3期25卷 351-355页

作者： G.M. Xie Z.Y. Ma l. Geng School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

6 mm thick ZK60 and ZK60-Y alloy plates were successfully friction stir welded （FSW） at a tool rotation rate of 1200 r/min and a traverse speed of 100 mm/min. FSW resulted in the dissolution of MgZn2 particles in the ZK60 and the breakup and dispersion of W-phase （Mg3Zn3Y2） particles in the ZK60-Y alloy, thereby leading; to a decrease in the hardness of the nugget zone （nz） for the ZK60 alloy and an increase in the hardness of the nz for the ZK60-Y alloy, respectively. While two FSW joints exhibited similar joint efficiency （87%-89% of ultimate tensile strengths of the parent materials）, the yield strength of the FSW ZK60-Y joint was substantially higher than that of the FSW ZK60 joint. The fracture occurred in the nz and the heat affected zone for the ZK60 and ZK60-Y joints, respectively, which were consistent with the lowest hardness distribution of the welded joints.

关键词： Friction stir welding Magnesium Microstructure Mechanical properties

Evolution of the Microstructure and Strength in the Nugget Zone of Friction Stir Welded SiCp/Al-Cu-Mg Composite

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Journal of Materials Science & Technology 2014年第1期30卷 54-60页

作者： D.Wang B.l.Xiao Q.Z.Wang Z.Y.Ma Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences University of Science and Technology of China

A 6 mm-thick SiCp/2009AI composite plate was successfully joined by friction stir welding （FSW） using an ultrahard material tool to investigate the evolution of the microstructure and the strength in the nugget zone （nz）. While some SiC particles were broken up during FSW, most of them rotated in the matrix. large compound particles on the interfaces were broken off during FSW, whereas the amorphous layer and small compound particles remained on the interfaces. The dynamically recrystallized AI grains nucleated on the surface of fractured SiC particles during FSW, forming nano-sized grains around the SiC particles. The yield strength of the nz decreased slightly due to the variation in the size, shape, and distribution of the SiC particles. The clean interfaces were beneficial to the load transfer between SiC particles and AI matrix and then increased the ultimate tensile strength of the nz.

关键词： Metal-matrix composites Friction stir welding Microstructure Mechanical properties