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231.
The kairomonal activity of the sex pheromones of three pine bast scales, Matsucoccus feytaudi, Matsucoccus josephi, and Matsucoccus matsumurae, as well as a new analog of the M. feytaudi sex pheromone, were investigated in pine forests of France, Portugal, and Italy. The response of the maritime pine bast scale predators, Elatophilus spp. and Hemerobius stigma, was used to test the influence of trapping methods, kairomone composition, and dose. Both predators showed significant attraction to all compounds except to the sex pheromone of M. josephi. Significant increase in captures was observed as a function of dose, and within the studied dose range, up to 2200 μg, no threshold saturation limits were observed for any of the attractive compounds. Trap design and size did not significantly influence predator captures, except for high population levels of Elatophilus crassicornis, when plate traps were more efficient than delta traps. Geographic variations were found in the kairomonal responses patterns of both predators, with the M. matsumurae sex pheromone being more attractive to the oriental populations from Corsica and Italy, whereas the western populations in Aquitaine and Portugal were more attracted to the M. feytaudi sex pheromone. 相似文献
232.
233.
圈闭评价与油气勘探决策 总被引:2,自引:0,他引:2
圈闭综合评价是依据圈闭条件、石油地质条件、经济条件,综合反映圈闭品质的过程.综合评价的结论可直观地、快捷地为勘探决策提供重要依据.本文在综合分析准噶尔盆地已知油气藏和已钻圈闭的石油地质研究成果的基础上,进行了评价参数归类和参数的选值方法的研究,这对提高圈闭评价结果的可靠性具有重要意义. 相似文献
234.
断层封堵性分析是在这样一条假设下进行的,即断层本身在油气运移过程中既可能起通道作用,也可能起遮挡作用,仅在断层两盘储层相互接触时才起通道作用,储、盖层接触时才起遮挡作用.其分析方法是首先沿断层走向切两盘的断层面剖面图,然后再把两盘剖面迭合,断层封堵性就清楚了。本方法适用于复杂断块、断鼻、断层-岩性圈闭地区的断层封堵性分析. 相似文献
235.
分析现有网络安全模式的不足,介绍诱骗网络的技术特点与实现方法,指出采用诱骗网络构建的安全体系所具备的优点,从而进一步提高校园网的网络安全系数. 相似文献
236.
J.C. Lee Y.P. KimZulkarnain S.J. LeeS.W. Lee S.B. KangS.Y. Choi Y. Roh 《Microelectronic Engineering》2011,88(7):1417-1420
The dielectric properties and reliability of fluorinated HfO2 have been studied. The fluorinated HfO2 dielectric treated by NF3 plasma showed improved dielectric characteristics but resulted in interfacial layer (IL) regrowth during the fluorine plasma treatment process, which led to an oxide capacitance reduction and poor electrical characteristics. Through the analysis of chemical composition and electrical characteristics, it has been revealed that the Hf-O bonds in HfO2 layer were converted to Hf-F bonds by the plasma treatment and then the dissociated oxygen diffused to the IL. In order to suppress the IL regrowth, newly fluorinated HfO2 has been developed. Reliability of fluorinated HfO2 dielectric was sharply improved without a decrease in the oxide capacitance at fluorine plasma treatment conditions of low power and temperature. 相似文献
237.
Photovoltaic devices based on Cu(In,Ga)Se2 with Cd-free buffer layer exhibit worse photovoltaic parameters and more pronounced transient behavior than standard CdS-buffered structures. In this work the electrical characteristics of the cells with ZnO buffer obtained by atomic layer deposition technique are compared to those of baseline CdS/CIGS cells. Persistent changes induced by light soaking and reverse-bias soaking in the current–voltage characteristics, admittance and DLTS spectra are analyzed. We discuss a role of buffer layer for the enhanced net doping in the interfacial region of absorber, Fermi-level pinning and conduction band offsets at the heterointerface for the photovoltaic performance of the cell. 相似文献
238.
H. Ikarashi K. Kitamura N. Kurosawa K. Horio 《Journal of Computational Electronics》2006,5(4):357-360
Two-dimensional transient simulations of AlGaAs/GaAs HFETs are performed in which substrate traps and surface states are considered.
When the drain voltage is raised abruptly, the drain current overshoots the steady-state value, and when it is lowered abruptly,
the drain current remains at a low value, showing drain-lag behavior. Turn-on characteristics are also calculated when both
the gate voltage and the drain voltage are changed abruptly, and quasi-pulsed I-V curves are derived from them. It is shown that the drain lag due to substrate traps could become a cause of so-called current
compression of the HFETs. It is also shown that gate lag due to surface states could become a major cause of the current compression. 相似文献
239.
Mono Trap具有萃取量大、操作简便等特点,在西瓜汁气味化合物萃取上具有一定优势。采用Mono Trap、热脱附结合气相色谱-嗅闻-质谱萃取分析热处理前后西瓜汁气味化合物变化。使用RGC18、RSC18、RGPS这3种吸附材料从鲜榨和热处理西瓜汁样品中分别鉴定出50种和71种气味化合物。通过实验对比这3种吸附材料的萃取效果,结果显示,RGC18对西瓜汁气味化合物的萃取效果最好,利用RGC18从鲜榨和热处理西瓜汁中分别萃取到41种和53种气味化合物。西瓜汁在热处理后,风味物质发生了很大变化,呈现苦杏仁味、皂化味和酸刺味的2-甲基丁醛、糠醛、辛醛、癸醛、(E)-2-庚烯醛、乙酸和甲酸等化合物的香气活力值增大;呈现清香、柠檬气味的己醛、β-环柠檬醛和(E,E)-2,4-壬二烯醛不能被嗅闻到。这些气味化合物的变化是导致西瓜汁热处理后出现异味的重要原因。 相似文献