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101.
2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide1,commonly known as Lawesson's reagent (LR,1a),and Japanese Reagent (1b),are not only thiating agent for diverse carbonyl compounds1-3, but also they undergoes ring-closure reactions with contain substrates containing two functional groups to give phosphorus heterocycles which contain phosphonothioyliene {C6H4-P(S)〈} moiety. These heterocyclic compounds are of potential interest as herbicides,insecticides,and fungicides4,5. Glycinamides are known as biologically active materials, for example, herbicides, plant-growth regulator6. In order to look for potent herbicides7 and to extent the use of Japanese Reagent to other bifunctional substrates,its reactions with 3-alkyl-glycinamides 2 have been investigated and found to give new phosphorus heterocycles which possess Significant selective herbicidal activity against rape. Here are our results. 相似文献
102.
α-Polychloroalkyl phosphoric dichlorides and their derivatives 2,3,4 has insecticidal activity1-4 and may be used as an intermediate to make other insecticides by reaction with alcohol, phenol, thiophenol or mercaptan. They can be prepared by various conventional methods of preparing phosphorus thioesters. Here we wish to report the addition reaction of tricovalent chlorophosphines with aldehydes containing withdrawing electron groups and its application in preparing of polychloroalkyl phosphorus dichlorides and their derivatives. The process can be represented by the following equation. 相似文献
103.
104.
SynthesesandCharacterizationofMetalComplexesOfL-Lysine-N,N,N',N'-tetraaceticAcidandL-Lysine-N,N,N',N'-tetramethylenephOsphoni... 相似文献
105.
ChemicalModificationofEVAforDrugReleaseApplicationHUYun-huaandZHUORen-xi(DeparrmentofChemistry,WuhanUniuersity,Wuhan,430072)(... 相似文献
106.
The four-fermion terms are introduced to investigate the effects of vector mesons in the σ model. A self-consistent solution is achieved in the mean field approximation by using the hedgehog ansatz.The static properties of nucleon are calculated, which are found to be in reasonable agreement with experiments. 相似文献
107.
108.
离心压缩机叶轮三维有限元强度分析系统 总被引:6,自引:0,他引:6
根据离心压缩机叶轮形状的特点,通过有效的网格自动划分和边界条件的处理,采用三维有限元方法进行了强度计算与分析,从而建立了离心叶轮三维有限元强度分析系统。对于叶轮与主轴之间的过盈配合,求出配合处由于变形而产生的弹性支力,以载荷形式施加于配合之处,由于计算时不加入主轴,从而减少了一,通过等厚度圆尖力的计算验证了有限元程序的可靠性,最二,对一个实际的三元流叶轮进行了计算,通过编制的后处理软件,对影响叶轮 相似文献
109.
The imaginary part of the off-shell nucleon self-energy at finite temperature in nuclear matter, where the polarization and correlation contributions of exchanges of the meson are taken into account, is investigated based on Walecka's meson-nucleon model and thermofield dynamics. The second order correction of temperature-dependent real part of the nucleon self-energy is calculated in terms of the dispersion relation. The Schrodinger equivalent potential of relativistic microscopic optical potential of a nucleon at finite temperature in nuclear medium is also studied. 相似文献
110.