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291.
EAG and behavioral responses of Helicoverpa armigera males to volatiles from poplar leaves and their combinations with sex pheromone 总被引:2,自引:0,他引:2
Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antennae of Helicoverpa armigera. When mixed with sex pheromone (Ph), some volatiles, e.g. phenyl acetaldehyde, benzyl alcohol, phenylethanol, methylsalicylate, linalool, benzaldehyde, (Z)-3-hexenol, (Z)-3-hexenylacetate, (Z)-6-nonenol, cineole, (E)-2-hexenal, and geraniol elicited stronger responses from male antennae than Ph alone. Wind tunnel bioassay demonstrated that various volatiles could either enhance or inhibit the effect of synthetic sex pheromone. (E)-2-hexenal, (Z)-3-hexenol and linalool in combination with Ph could not induce any male to land on source at all, whereas phenyl acetaldehyde, benzaldehyde, (Z)-6-nonenol and salicylaldehyde combined with Ph enhanced male response rates by 58.63%, 50.33%, 51.85% and 127.78%, respectively, compared to Ph alone. These results suggested that some volatiles shouldmodify sex pheromone caused behavior and that some of them could possibly be used as a tool for disrupting mating or for enhancing the effect of synthetic sex pheromone in the field. 相似文献
292.
Peat record reflecting Holocene climatic change in the Zoigê Plateau and AMS radiocarbon dating 总被引:2,自引:0,他引:2
Weijian?ZhouEmail author Xuefeng?Lu Zhengkun?Wu Lin?Deng A.?J.?T.?Jull D.?Donahue W.?Beck 《科学通报(英文版)》2002,47(1):66-70
Through the use of reliable AMS dating of high resolution (15–30 years) peat and the establishment of monsoon climate proxies
sequence, we have been able to recognize several cold, dry events in the Tibetan Plateau during the Holocene. The more obvious
ones occurred around 12800, 11300, 10200, 9580, 8900, 6400, 4400, 3700, 2800 and 1500 cal. aBP. These events correlate well
with both ice rafting events recorded in high latitude North Atlantic Ocean sediment cores and cooling events in the low latitude
SST. Spectral analysis indicates high frequency climate variation on centennial-millennial time scale during the Holocene.
This further reflects Holocene climate instability and the existence of centennial-millenium scale rhythm in mid latitude
areas as well. 相似文献
293.
Lu?PingEmail author Liu?Bin Zhang?Zhe Wu?Feng Deng?Nan-shengEmail author 《武汉大学学报:自然科学英文版》2003,8(4):1147-1152
Inclusion complex of Orange II with β-Cyclodextrin (β-CD) and the anti-photolysis effect under UV-light were investigated.
The molar ratio of inclusion complex of β-Cyclodextrin and Orange II is 1∶1. The formation constantK = 1.236×103 L/mol was determined by the UV and Fluorescence spectra respectively, which was quite in accordance with the calculation
with a modified Benesi-Hildbrand equation. The inclusion complex was characterized by the IR spectra and the molar ratio of
inclusion complex is 1∶1 too. The formation constantK = 1.266×103 L/mol was determined by1H NMR analysis and was nearly the same by UV and fluorescence spectra. The photocatalytic decolorization rate of Orange II
solutions containing β-CD and TiO2 was smaller by 51.9% than that of the Orange II solutions only containing TiO2, while in the case of direct photolysis of Orange II solutions, β-CD can lower the photolysis rate by 48.1% under UV-light.
This result indicates β-CD can inhibit the photolysis and photocatalytic decolorization of Orange II under UV-light. The β-CD
inclusion complex was found to be persistent to UV-light photolysis.
Foundation item: Supported by the National Natural Science Foundation of China (20177017)
Biography: Lu Ping (1958), male. Associate professor, research direction: environmental photochemistry. 相似文献
294.
295.
2006年5—9月,采用焦点取样法和全事件观察法对放归鳄蜥的昼间活动时间分配进行了初步研究.结果表明:在放归鳄蜥昼间活动时间分配中,在穴占61.02%±30.56%、静栖占36.72%±19.71%、运动占1.55%±0.96%、摄食占0.12%±0.08%、其他行为占0.59%±0.16%.晴天和阴天条件下放归鳄蜥的在穴、静栖、运动、摄食活动时间存在显著性差异(P﹤0.05);圈养鳄蜥和放归鳄蜥的在穴、静栖、摄食活动存在显著性差异(P﹤0.05);雌、雄及亚成体放归鳄蜥间的在穴、静栖、运动活动存在显著性差异(P﹤0.05).结果也表明,长期人工饲养对鳄蜥的摄食活动产生了较大影响. 相似文献
296.
结合工程项目管理的实际,以有效控制项目成本为目标,引出工程管理中项目经理应具备的业务素质及其管理制度和措施,并阐述其要求及作用,说明其在控制项目成本实施过程中的重要地位。 相似文献
297.
汉字教学在语文教学中是一块"鸡肋",存在着许多问题,有必要全面提升汉字教学的系统性和可操作性。本文试图从汉字本身的规律及其延伸拓展的作用方面,探讨汉字教学与语文素养之间的关系,进而促进汉字教学的发展。 相似文献
298.
针对《电工学》课程具有课时数少,内容覆盖面广,授课对象为非电专业学生的特点,利用我校《电工学》精品课程网站,实现优质教学资源共享,使课堂教学在空间、时间及教学内容上得到延伸。 相似文献
299.
DENG Jun WU ZhiJun HUANG ChengJie FENG Wei LI LiGuang 《科学通报(英文版)》2007,52(2):277-283
Auto-ignition characteristics of high-pressure diesel spray in the controllable active thermo-atmos-phere (CATA) were studied with a high-speed camera video system. Multi-point autoignition phe-nomenon of diesel spray in the CATA was observed and the influence factors of the autoignition were analyzed. The stabilization mechanisms of the spray flame in different coflow temperatures were also discussed. The stabilization of the flames was controlled by different factors: autoignition phenomenon in low coflow temperature and flame spread in high coflow temperature. The test results also show that the autoignition delay depends strongly on the coflow temperature and has nonlinear relationship with the temperature. Autoignition delay decreases by almost 10 ms from 16.9 to 7.1 ms when the coflow temperature increases from 996 to 1048 K and only 4 ms from 1048 to 1101 K. The injection parameters in terms of nozzle diameter, injection pressure and pump speed, have some effects on autoignition delay while these effects depend on the coflow temperature. The significant effect lies in low coflow temperature. The injection parameters influence the autoignition delay because it can shorten the physical delay by improving the spray quality and enlarging the spray angle or penetration rate to im-prove mixture quality. 相似文献
300.
某工程桩基问题的分析与处理 总被引:3,自引:0,他引:3
从地质条件和施工技术等方面出发,详细分析了某工程桩基出现的裂缝、偏移等病害,并提出了管径内灌芯补强,加大承台和补桩等处理措施,试验证明处理方案是可行的. 相似文献