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31.
针对标准粒子群算法存在的局部最优、早熟和慢收敛等问题,提出了一种新的粒子群更新方法。改进了算法惯性权重,引入一种新的更新方式;借鉴蜣螂优化算法中蜣螂滚球、繁殖、觅食和偷窃行为,将基本粒子群的操作划分为寻优、变异、波动和跳跃,从而提高了算法的全局寻优能力和收敛速度,并避免了早熟问题。通过与其他9种智能算法进行实验对比表明,在10个基准测试函数中,基于蜣螂优化的改进粒子群算法在寻优能力和收敛速度方面表现出色,证实了该算法的优越性。 相似文献
32.
The normal levels and types of glycoalkaloids found in commercial varieties of potato (Solanum tuberosum) appear to present no hazard to human health. However when wild Solanum species are used in breeding endeavors, new and untested glycoalkaloids may be introduced. Recent studies of domestic crosses with a wild Solanum oplocense accession indicated that the levels of a non‐indigenous glycoalkaloid appeared associated with reduced defoliation by the Colorado potato beetle. The non‐indigenous glycoalkaloid was isolated from foliage of the wild S. oplocense accession and unambiguously characterized by high‐resolution electrospray ionization mass spectrometry and NM analysis as the glycoalkaloid dehydrocommersonine. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
33.
Kenji Shimomura Hiroyuki Koshino Noriko Matsumoto Kanju Ohsawa 《Tetrahedron letters》2010,51(52):6860-6862
(E)-6-Ethyl-2,10-dimethyl-5,9-undecadienal was identified from female seed beetle, Callosobruchus rhodesianus (Pic), as an electroantennographic-detection (EAD) active compound in the male. The ratio of the (E)-6-ethyl-2,10-dimethyl-5,9-undecadienal and (3S,6E)-2,3-dihydrohomofarnesal, previously identified as a sex attractant pheromone, was estimated at approximately 1:4.5. In combination with the stereoisomer-activity relationship of 2,3-dihydrohomofarnesal, we suggest that this new compound might function as a minor sex attractant pheromone in C. rhodesianus. 相似文献
34.
Chlorophorus caragana Xie & Wang is a destructive wood-boring beetle that damages Caragana spp. bushes and is distributed in desert areas in north-west China. Using scanning electron microscopy and transmission electron microscopy, we observed the morphology and ultrastructure of antennal and posterior abdominal sensilla in C. caragana females, to discuss the putative functions of these sensilla in host location and oviposition behaviors.In total, seven types (24 subtypes) of sensilla were located on the antenna and posterior abdomen. On the antenna, there were Böhm's bristles (BB.); four subtypes of sensilla chaetica (Ch.1–Ch.4) characterized by non-porous surfaces and sensillum-lymph cavities without dendrites; two subtypes of sensilla trichodea (Tr.1 and Tr.2) with a tip pore and dendrites surrounded by dendritic sheaths; dome-shaped sensilla (Dom.) emerging from a deep cavity with one tip pore; four subtypes of sensilla basiconica (Ba.1–Ba.4) and one type of sensilla auricillica (Au.) with a porous cuticular surface and dendrites in the sensillum-lymph cavity; and one type of sensilla styloconica (Sty.) with grooves on the cuticular wall. On the posterior abdomen, there were four subtypes of sensilla chaetica (Ch.5–Ch.8); three subtypes of sensilla trichodea (Tr.3–Tr.5); and three subtypes of sensilla basiconica (Ba.5–Ba.7; Ba.5 had no groove in the cuticular wall, Ba.6 had one tip pore, and Ba.7 was located in a cuticular cavity). The antennal sensilla were believed to be mechanosensitive, chemosensitive, and sensitive to humidity and temperature, and to play roles in mating, host location and oviposition. The abdominal sensilla are believed to be related to oviposition behaviors. 相似文献
35.
触破式微胶囊农药的降解和残留及对天牛的药效 总被引:5,自引:1,他引:4
用HPLC法对触破式微胶囊农药的残留量及降解规律进行测定。结果表明 ,施药 45d后残留农药为本底值的 36.6% ,这与杨树天牛生测得到的规律完全吻合的 ,施药 38d生测时 ,光肩星天牛和黄斑星天牛的死亡率为 90 %。说明了触破式微胶囊农药具有残效期长、使用安全、杀虫效果好和对环境安全的特点 ,是防治天牛类害虫较为理想的农药剂型 相似文献
36.
A simple synthesis of a diastereomeric mixture of 7-hydroxy-4,6-dimethylnonan-3-ones was carried out. In the biological action,
it is an analog of serricornin, the sex pheromone of the cigarette beetle (Lasioderma serricorne).
Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1218–1221, May, 2005. 相似文献
37.
【目的】松墨天牛是一种重要的松林蛀干害虫,也是亚洲地区松材线虫最主要的媒介昆虫,研究松墨天牛取食能力与环境温度、天牛性别以及体质量的关系,分析松墨天牛产卵能力与松树树皮厚度、树干直径以及天牛体质量的关系,为松墨天牛的科学防治提供参考。【方法】从养虫笼中收集天牛,选择体质量(M)在0.3 g≤M<0.6 g的松墨天牛放置在昆虫培养箱中,设置4个温度梯度(25、30、35和40℃),比较不同温度条件下天牛的取食能力;选取体质量相似的5头雌成虫和5头雄成虫于昆虫培养箱中,比较天牛雌雄成虫取食差异;选择不同体质量(M<0.3 g, 0.3 g≤M<0.6 g和M≥0.6g)天牛放置在温度相同的昆虫培养箱中,比较不同体质量天牛取食能力。在养虫桶中放入直径(D)不同(2.0 cm相似文献
38.
V. I. Bykov A. R. Goletiani T. A. Butenko E. Sh. Finkelshtein 《Russian Chemical Bulletin》2004,53(11):2650-2652
A new synthesis of (Z,E)-undec-5-enoic acids with the natural isomer composition Z/E = 85 : 15, the sex pheromone of the varied carpet beetle Anthrenus verbasci was developed based on co-metathesis of cycloocta-1,5-diene and ethylene.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2540–2542, November, 2004. 相似文献
39.
核桃扁叶甲是核桃、枫杨等胡桃科植物的一种严重害虫,常将寄主树叶吃光,对树的生长有很大的影响,本文经过前后三年来的观察研究,总结、记述了该虫生物学特性及防治方法。 相似文献
40.