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新型植物杀菌剂--苯并噻二唑类植物抗病诱导剂 总被引:5,自引:0,他引:5
植物抗病诱导剂是近年来发现的一种新型植物杀菌剂,苯并噻二唑类(BTH)就是其中重要的一类。对近年来BTH研究情况作一简要综述。 相似文献
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Alekseevskii-Tate revisited:An extension to the modified hydrodynamic theory of long rod penetration
LAN Bin & WEN HeMing CAS Key Laboratory for Mechanical Behavior Design of Materials University of Science Technology of China Hefei China 《中国科学:信息科学(英文版)》2010,(5)
The modified hydrodynamic theory of long rod penetration into semi-infinite targets was established independently by Alek-seevskii and Tate over forty years ago and since then many investigators contributed much to the development of the high speed penetration mechanics.However,in all the models proposed so far,the target resistance Rt is not well defined and usually determined by adjusting it until the predicted depth of penetration comes to an agreement with experimental data.In this paper,assumptions are... 相似文献
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在施工建设中,实时准确地观测、分析和预报建筑物的沉降变形对最后施工的成功与否有着很大的影响。在变形监测中经常遇到数据信息不完备的情况,而灰色系统理论则是用来解决此问题的有效方法。建立了灰色预测模型,并将其应用于苏南运河整治工程中新建驳岸的沉降监测分析和预测中,预测效果较好。 相似文献
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The Helimak of USA is a plasma physics experimental device designed and built by CASIPP.Its configuration of magnetic field is of very importance during the operation of this device.In this paper,the influence of magnetic permeability on configuration of magnetic field will be discussed due to the effect of weld metal in the vacuum vessel of Helimak,and some conclusion is useful for some engineering designs of the fusion experimental device. 相似文献
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Measurements of boundary parameters and their fluctuations have been performed in ohmic (OH) plasma and Ion Bernstein Wave (IBW) and Lower Hybrid Current Drive (LHCD) enhanced confinement plasma using a pneumatically driven Langmuir probe array on HT-7 toka-maX. In the enhanced confinement plasma~ the gradients of electron density and temperature become higher and a transport barrier comes into being in the vicinity of the limiter. The boundary potential shows a clear modification in the same region. The fluctuation levels are significantly depressed and the coherences between fluctuations are reduced evidently in the enhanced plasma.Meanwhile, we obtained the spectral features and the poloidal phase velocity of fluctuations us-ing a two-point correlation technique and found obvious modifications of the turbulence and the poloidal flow. The results suggest that the improved confinement in the IBW and LHCD enhanced plasma is at least partially due to the modification of the boundary parameters and the suppression of the boundary fluctuations and fluctuation induced fluxes. 相似文献
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Tritium self-sustainment, which will meet the fuel requirement of fusion reactor, is one of the key issues of fusion power development. The tritium breeding performances of various tritium-breeding materials are compared based on a series of neutronics calculations using three-dimensional Monte Carlo neutron-photon transport code MCNP/4C with the IAEA FENDL-2 data library. The effects of the dimensions of the tritium-breeding zone and the enrichment of 6Li on Tritium Breeding Ratio (TBR) are analyzed. The effects of Be as a neutron multiplier on TBR are also calculated. 相似文献
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汉语三字词声调的模式分析 总被引:4,自引:0,他引:4
汉语三字词的声调模式是复杂的。本文对4 男4 女各192 个三字词的声调进行分析,选择各音节的头尾差和相对调位比为特征,在进行特征抽取、统计和分析的基础上,研究了三字调整声调的模式和变调规则。本文的结果对三字词和连续语音声调的识别具有重要价值。 相似文献
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