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利用复函数的积分及积分变换的知识对∫^+∞ 0sinx/xdx给出了五种求解方法,方法简单,得到满意的结果. 相似文献
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Imidacloprid in processed tea and tea liquor 总被引:1,自引:0,他引:1
Sanyal N Hazra D Pal R Somchaudhury AK Chowdhury A 《Journal of Zhejiang University. Science. B》2006,7(8):619-622
Imidacloprid is a newly introduced broad-spectrum chloronicotinyl insecticide and will find its way in agricultural production, particularly in Asia. However, information on the fate of imidacloprid in crop plants is lacking. The degradation of imidaclopnd in processed CTC tea and tea liquor was investigated in the present study in which imidacloprid was applied at recommended application rate (30.0 g a.i./ha) and twice the recommended application rate (60.0 g a.i./ha) for three consecutive seasons. Imidacloprid was rapidly dissipated in processed tea following first order reaction kinetics at all application rates and had half-lives of 0.9 1-1.16 d with the residue in tea liquor found to be below detectable limit on 3rd day samples. The study revealed that imidacloprid is safe for human consumption and will not pose any residual toxicity problem. 相似文献
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梁华 《喀什师范学院学报》2009,30(6):13-14
利用初等数论的一些基本知识和重要结论,证明了单位群里非单位元的阶都是2的剩余类环Zn只有Z3,Z4,Z6,Z8,Z12和Z24. 相似文献
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本文介绍一种检测蔬菜中氧化乐果残留的简便方法。以生菜为样品 ,通过其准确度、灵敏度和精密度分析 ,并与国家标准方法———气相色谱法进行比较和实验学评价 ,结果表明 :该方法对氧化乐果的回收率达 80 %以上 ;最低检测限量为 0 .5mg·kg- 1;多次平行测定变异系数小于 6 % ,其可以满足半定量分析的要求。 相似文献
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从PPP项目残值风险的知识管理的角度出发,构建残值风险的本体知识库并结合具体案例进行应用分析。通过对PPP项目残值风险的文献回顾,对该风险的形成机理进行研究,建立PPP项目残值风险的知识框架。同时,定义知识框架里各个概念及其结构层次,并对概念之间的关系和属性进行知识表示,再根据SWRL语言对概念关系进行适当推理。最后,论文采用本体编辑软件Protégé构建Sky大桥项目的残值风险本体知识库,对知识进行更有效的表达,促进其可共享性和可传递性,实现更深入的信息查询和数据处理功能。 相似文献
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Residue-residue contacts are very important in forming protein structure. In this work, we calculated theaverage probability of residue-residue contacts in 470 globular proteins and analyzed the distribution of contacts in thedifferent interval of residues using Contacts of Structural Units (CSU) and Structural Classification (SCOP) software. Itwas found that the relationship between the average probability -PL and the residue distance L for four structural classes ofproteins could be expressed as lgPL=a b×L, where a and b are coefficients. We also discussed the connection between twoaspects of proteins which have equal array residue number and found that the distribution probability was stable (or un-stable) if the proteins had the same (or different) compact (for example synthase) in the same structural class. 相似文献
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利用复函数的积分及积分变换的知识对∫^+∞ 0sinx/xdx给出了五种求解方法,方法简单,得到满意的结果. 相似文献
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