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八角茴香提取物对长角扁谷盗的触杀和驱避活性 总被引:1,自引:0,他引:1
为开发环境友好的植物源杀虫剂,以3种有机溶剂采用冷浸法对八角茴香干果中的生物活性物质进行提取,采用滤纸药膜法测定提取物对长角扁谷盗成虫的触杀和驱避活性.结果表明:处理剂量越高,试虫死亡速度越快;用148.63 μg/cm2剂量处理72 h后,甲醇、乙酸乙酯和石油醚提取物对试虫的致死率分别为87.85%、90.98%和94.44%;甲醇、乙酸乙酯和石油醚提取物处理长角扁谷盗成虫72 h后的LD5o分别为28.21、23.51和19.23 μg/cm2,触杀效果依次为:石油醚提取物>乙酸乙酯提取物>甲醇提取物.提取物的剂量越高,其驱避作用越大;在各提取物剂量为123.46 μg/cm2时,对长角扁谷盗处理72 h后的平均驱避率以乙酸乙酯提取物最高,达73.22%,驱避等级为Ⅳ级. 相似文献
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介绍了Schllkopf手性试剂的合成工艺,以D-缬氨酸为原料,经保护,氯甲酸叔丁酯活化后,与甘氨酸甲酯盐酸盐反应得甲基-N-(叔丁氧基羰基)-D-缬氨酸甘氨酯;酯加热成环后,与三甲氧嗡四氟化硼盐反应得Schllkopf醚,总收率为51.8%。 相似文献
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关于用Protel 99 SE 绘制Word文档电路图的研究 总被引:2,自引:0,他引:2
姚四改 《安徽电子信息职业技术学院学报》2004,3(2):74-75
本文针对电子类专业教师在用Word编辑类似考试试卷文档时,所面临的电路图难画问题,提出了利用Protel 99 SE电路设计软件画电路图,而后再将电路图调入word中的一种比较实用的图文混排方法。 相似文献
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Akio Kobayashi Shigeo Morimoto Yoshiari Shibata Kyohei Yamashita Makoto Numata 《Journal of chemical ecology》1980,6(1):119-131
cis-Dehydromatricaria ester (cis-DME) inSolidago altissima, andcis-matricaria ester (cis-ME),trans-matricaria ester (trans-ME), andcis-lachnophyllum ester (cis-LE) inErigeron spp. show strong growth inhibitory effects on other plants. Thecis- andtrans-DMEs were found in soil at the border ofS. altissima communities in concentrations that were inhibitory to test plants. Among four species ofErigeron, the most dominant plant,E floribundus, showed the highest concentrations of the esters. From the results of our experiments, we conclude that these polyacetylenes are probably allelopathic substances with ecological importance. 相似文献
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研究大孔树脂纯化马兰总黄酮树脂吸附特性及工艺条件及参数。文中分别进行静态吸附、静态解吸、静态吸附动力学过程(Lagergren准一级动力学方程)、静态吸附等温曲线(Langmuir和Freundich等温吸附方程)、动态吸附实验,从7种大孔树脂中筛选用于马兰总黄酮分离的最佳树脂,并系统研究最佳大孔树脂分离纯化的吸附性能和最优洗脱参数。结果表明:D101型大孔树脂为分离马兰黄酮类组分最佳树脂,其分离的最佳工艺为总黄酮浓度为9.36 mg/mL的样液,以3 BV/h的流速,控制pH值为4~5上柱,用75%乙醇以3 BV/h用量进行洗脱,可获得样品总黄酮纯度达70%以上。 相似文献
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Joseph A. Ball Philip T. Carroll Yoichi Uetake 《Mathematics of Control, Signals, and Systems (MCSS)》2008,20(1):37-79
We give a further elaboration of the fundamental connections between Lax-Phillips scattering, conservative input/state/output
linear systems and Sz.-Nagy-Foias model theory for both the discrete- and continuous-time settings. In particular, for the
continuous-time setting, we show how to locate a scattering-conservative L
2-well-posed linear system (in the sense of Staffans and Weiss) embedded in a Lax-Phillips scattering system presented in axiomatic
form; conversely, given a scattering-conservative linear system, we show how one can view the space of finite-energy input-state-output
trajectories of the system as the ambient space for an associated Lax-Phillips scattering system. We use these connections
to give a simple, conceptual proof of the identity of the scattering function of the scattering system with the transfer function
of the input-state-output linear system. As an application we show how system-theoretic ideas can be used to arrive at the
spectral analysis of the scattering function. 相似文献
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Harry M. Sneed 《Informatik-Spektrum》1996,19(3):133-140
Eingegangen am 29.04.1995, in überarbeiteter Form am 17.01.1996 相似文献
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