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松材线虫是美国值得重视的一种病原体

湖北林业科技 1984年第4期 42-45页

作者： m.j.Wingfield r.A.Blanchette 谢翼伟

松材线虫 Bersaphelenchus xylophilu-s,在日本对本地松已造成严重危害。最近美国将线虫鉴定为一种病原体。病理学家们予测,此线虫也许会威协这里的森林。有不少的证据表明,线虫除了能导致这个国家的国外松死亡之外。如欧洲赤松(Pinus s... 详细信息

松材线虫 Bersaphelenchus xylophilu-s,在日本对本地松已造成严重危害。最近美国将线虫鉴定为一种病原体。病理学家们予测,此线虫也许会威协这里的森林。有不少的证据表明,线虫除了能导致这个国家的国外松死亡之外。如欧洲赤松(Pinus sylestris)和黑松(P、thunbergii),还可引起从未受到线虫侵染的当地松树死亡。传播线虫的媒介昆虫由于在其产卵期间可将线虫传播到伐倒木和濒死立木上,所以在并非主要由线虫致死的植株上也能出现线虫。在美国,昆虫在产卵期间传播线虫能解释线虫在植株遭到其它因子危害后才进入寄主上。

关键词：松材线虫立木伐倒木欧洲赤松病原物病原体美利坚合众国北美洲美国

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对流性风暴及其天气现象的自动化预报

气象科技 1988年第6期 6-10页

作者： r.m.reap j.P.Charba 夏建国

一、引言自本世纪七十年代中期以来,作为日常业务已向国家天气局(NWS)的天气预报中心、民航机场和全国各地的多种其它用户发布雷暴、局地强风暴及由其引起的天气现象,如龙卷、大冰雹、破坏性强风和暴雨的短期(6—36小时)与甚短期(2—6... 详细信息

一、引言自本世纪七十年代中期以来,作为日常业务已向国家天气局(NWS)的天气预报中心、民航机场和全国各地的多种其它用户发布雷暴、局地强风暴及由其引起的天气现象,如龙卷、大冰雹、破坏性强风和暴雨的短期(6—36小时)与甚短期(2—6小时)的客观预报。种类繁多的预报产品是采用模式输出统计(mOS)技术与多元筛选回归方法得到的。

关键词：模式输出局地强风暴龙卷客观预报概率预报对流天气风暴天气落区民航机场雷达资料

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超载交通对道路路面性能的影响

中外公路 2015年第3期35卷 338-342页

作者： j. C. Pais S. I. r. Amorim m. j .C. minhoto 孙吉书耿晓婷孙建诚不详河北工业大学土木工程学院天津市300401 河北省土木工程技术研究中心

道路交通由大量不同类型的车辆组成,在路面设计中,应用卡车因子将这些车辆对路面的破坏转化成具有相同破坏的标准轴考虑,将卡车转化为标准轴的卡车因子或将各轴转化为标准轴的当量轴载,换算系数是通过平均轴载定义的,这一过程中包括轴... 详细信息

道路交通由大量不同类型的车辆组成,在路面设计中,应用卡车因子将这些车辆对路面的破坏转化成具有相同破坏的标准轴考虑,将卡车转化为标准轴的卡车因子或将各轴转化为标准轴的当量轴载,换算系数是通过平均轴载定义的,这一过程中包括轴载大于最大限值的车辆,也有相当数量总重超载的车辆,这些车辆导致路面显著破坏,增加了路面建设和维修费用。该文通过研究不同车辆在5种不同沥青层厚度和5种不同路基刚度模量的一组路面上的卡车因子,来探讨超载车辆对道路路面的影响。研究显示:与法定荷载的相同车辆相比,超载车辆的存在会将路面成本提高100%以上。

关键词：路面卡车荷载系数超载

PErSPECTIVES IN mECHANICS OF HETErOGENEOUS SOLIDS

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Acta mechanica Solida Sinica 2011年第1期24卷 1-26页

作者： C.Q. Chen j.Z. Cui H.L. Duan X.Q. Feng L.H. He G.K. Hu m.j. Huang Y.Z. Huo B.H. ji B. Liu X.H. Peng H.j. Shi Q.P. Sun j.X. Wang Y.S. Wang H.P. Zhao Y.P. Zhao Q.S. Zheng W.N. Zou Department of Engineering mechanics AML Tsinghua University Beijing 100084 China Academy of mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100190 China State Key Laboratory for Turbulence and Complex System and Department of mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China CAS Key Laboratory of mechanical Behavior and Design of materials University of Science and Technology of China Hefei Anhui 230026 China School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Institute for Advanced Study Nanchang University Nanchang 330031 China Depariment of mechanics and Engineering Sciences Fudan University 220 Handa Road Shanghai 200433 China Department of mechanical Engineering Hong Kong University of Science and Technology Hong KongChina Department of mechanical Engineering Hong Kong University of Science and Technology Hong Kong China Institute of Engineering mechanics Beijing Jiaotong University Beijing 100044 China State Key Laboratory of Nonlinear mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The micro- and Nano-mechanics Working Group of the Chinese Society of Theoretical and Applied mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in january 2010. The international journal, Acta mechanica Solida Sinica, is de- voted to all fields of solid mechanics and relevant disciplines in science, technology, and engineering, with a balanced coverage on analytical, experimental, numerical and applied investigations. On the occasion of the 30Tm anniversary of Acta mechanica Solida Sinica, its editor-in-chief, Professor Q.S. Zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids, with a particular emphasis on the recent research development results of Chinese scientists. Their reviews are organized into five research areas as reported in different sections of this paper. ~I firstly brings in fo- cus on micro- and nano-mechanics, with regards to several selective topics, including multiscale coupled models and computational methods, nanocrystal superlattices, surface effects, micromechanical damage mechanics, and microstructural evolution of metals and shape memory alloys. ~II shows discussions on multifield coupled mechanical phenomena, e.g., multi-fields actuations of liquid crystal polymer networks, mechanical behavior of materials under radiations, and micromechanics of heterogeneous materials. In ~III, we mainly address the multiscale mechanics of biological nanocomposites, biological adhesive surface mechanics, wetting and dewetting phenomena on microstructured solid surfaces. The phononic crystals and manipulation of elastic waves were elaborated in ~IV. Finally, we conclude with a series of perspectives on solid mechanics. This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.

关键词： heterogeneous materials smart materials biological materials multiscale mechanics micro- and nano-mechanics damage and fracture constitutive relation elastic wave surface effects

The development of Taqman real-time PCr assays for the quantitative detection of marek’s disease virus type 1（mDV-1）,rispens CVI988 and HVT DNA in white blood cells,organs and feathers of chickens

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The development of Taqman real-time PCR assays for the quant...

Provisioning Intelligent Water Wave Optimization Approach for Underwater Acoustic Wireless Sensor Networks

The 15th World Veterinary Poultry Congress

作者： G.j.Wellenberg j.Brinkhof W.j.m.Landman GD Animal Health Service LtdDeventerThe Netherlands. GD Animal Health Service LtdDeventerThe Netherlands. GD Animal Health Service LtdDeventerThe Netherlands.

＜正＞Newly developed real-time PCr assays enables us to determine the rispens CVI988 and HVT virus loads in blood and feather samples after vaccination（Islam et al.,2004）.The purpose of this study was to develop and evaluate Taqman real-time PCr assays to determine the absolute marek’s Disease virus type 1（mDV-1）,

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Computer Systems Science & Engineering 2022年第11期43卷 625-641页

作者： m.manikandan A.rajiv Kannan Department of Computer Science and Engineering Vidhyaa Vikas College of Engineering and TechnologyTiruchengodeNamakkalTamilnaduIndia Department of Computer Science and Engineering KSR College of Engineering(Autonomous)TiruchengodeNamakkalTamilnaduIndia

In the Acoustics channel,it is incredibly challenging to offer data transfer for time-sourced applications in an energy-efficient manner due to higher error rate and propagation ***,conventional re-transmission over any failure generally initiates significantly larger end-to-end delay,and therefore it is not probable for time-based ***,standard techniques without any re-transmission consume enormous *** investigation proposes a novel multi-hop energy-aware transmission-based intelligent water wave optimization *** ensures reduced end-to-end while attaining potential amongst overall energy efficiency end-to-end packet *** merges a naturally inspired meta-heuristic approach with multi-hop routing for data packets to reach the *** appropriate design of this meta heuristic-based energy-aware scheme consumes lesser energy than the conventional one-hop transmission strategy without ***,there is no hop-by-hop re-transmission *** proposed model shows only lesser delay than conventional methods with *** work facilitates extensive work to carry out the proposed model performance with the mATLAB simulation *** results illustrate that the model is exceptionally energyefficient with lesser packet *** 500 nodes,the packet delivery ratio of proposed model is 100%,average delay is reduced by 2%,total energy consumption is 8 j,average packet redundancy is 1.856,and idle energy is *** proposed model outperforms existing approaches like OSF,AOr,and Dmr respectively.

关键词： Acoustic applications energy efficiency network communications underwater sensor networks meta-heuristic approach intelligent water wave optimization

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大豆花叶病毒株系的鉴定

南京农业大学学报 1983年第3期 36-40页

作者：许志纲,r.m.Goodman,j.E.Polston 南京农学院植物病理教研组美国伊利诺斯大学美国伊利诺斯大学

从1981年10月至1982年5月,在美国伊利诺斯大学植病系温室中接种并鉴定了中国大豆花叶病毒的标样23个。根据它们在9个抗性不同的鉴别品种上的反应差异,分为10个株系群,即在原来 G1—G7的7群基础上增设3个群,它们是 G8、G9和G10,分别以 C1... 详细信息

从1981年10月至1982年5月,在美国伊利诺斯大学植病系温室中接种并鉴定了中国大豆花叶病毒的标样23个。根据它们在9个抗性不同的鉴别品种上的反应差异,分为10个株系群,即在原来 G1—G7的7群基础上增设3个群,它们是 G8、G9和G10,分别以 C16,S6和 C283个标样为代表。这3群6个毒株的毒力要比美国7群的都强些,一些在美国认为是高抗或免疫的品种,在感染中国毒株后表现为黄色斑或叶脉坏死的症状。用十二烷基磺酸钠（S.D.S）配制的琼脂凝胶平板进行奥氏双扩散血清学检验,大豆花叶病毒与相应的抗血清发生沉淀反应,乳白色沉淀带清晰可见。

关键词：大豆花叶病毒株系标样花叶毒株毒力标准样品毒性大豆品种鉴别品种

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人工授精中家兔生产的分类管理

中国养兔杂志 1995年第2期 38-40页

作者：王勇 reboller Pilar G Alvarino j.m.r Ubilla

用加利福尼亚兔和新西兰白兔的杂交后代共１３０只在同一天以１ｍｌ稀释精液进行人工授精，开始１３个月的研究，实验期间，窝产仔数不足８只的母兔（设为Ｍ１组）在其产后第３～４天配种，窝产仔数达到８只的母兔（设为Ｍ２组）在其产... 详细信息

用加利福尼亚兔和新西兰白兔的杂交后代共１３０只在同一天以１ｍｌ稀释精液进行人工授精，开始１３个月的研究，实验期间，窝产仔数不足８只的母兔（设为Ｍ１组）在其产后第３～４天配种，窝产仔数达到８只的母兔（设为Ｍ２组）在其产后第１０～１１天配种；所有未配上的母兔（设为Ｍ３组）都视作假孕，并在上次配种后第２４天再次配种。初配兔第一次授精时间的４月龄。整个实验期间共进行了１６７９次配种。

关键词：兔家兔人工授精分类管理

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墙角节点声传递机理的探讨

广西大学学报（自然科学版） 2002年第3期27卷 236-239页

作者：黄险峰吴硕贤 r.j.m.Craik 华南理工大学建筑学系广东广州510640 赫瑞瓦特大学建筑工程系

对建筑中墙角节点的声传递进行了理论分析 ,计算了其声透射系数和隔声量 .计算结果和实验测试有良好的一致性。

关键词：声传递机理墙角节点加速度级差声透射系数隔声量建筑隔声