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51.
Gas chromatographic–mass spectrometric analyses of the scent gland secretions of Siro duricorius and S. exilis (Opiliones, Cyphophthalmi, Sironidae) revealed a set of 24 components, comprising a series of saturated and unsaturated methyl ketones (C11–C15) and four naphthoquinones. Whereas the scent gland secretions of S. duricorius, collected in Austria, and S. exilis from USA were qualitatively nearly indistinguishable (with the exception of acetophenone that was specific to S. duricorius), they distinctly differed in their relative quantitative compositions: major components of the secretion of S. duricorius were 7-tridecen-2-one, tridecan-2-one, undecan-2-one, 1,4-naphthoquinone, 6-methyl-1,4-naphthoquinone (tentatively identified only), and 4-chloro-1,2-naphthoquinone. In contrast, in S. exilis a compound tentatively identified as 6-methyl-4-chloro-1,2-naphthoquinone was present in large amounts (in S. duricorius a trace component), whereas undecan-2-one only occurred in minor quantities. Secretion profiles of juveniles and adults (both sexes) of each species showed high correspondence.This is the first report on the chemistry of scent gland secretions of the opilionid suborder Cyphophthalmi. 4-Chloro-1,2-naphthoquinone was identified as a new exocrine product of arthropods, whereas 1,4-naphthoquinone and the tentatively identified 6-methyl-1,4-naphthoquinone are known constituents of exocrine secretions from one species of palpatorid opilionids, Phalangium opilio. In contrast, all ketones identified were new for opilionid scent glands, although similar ketones are characteristic of scent gland secretions of palpatorid genera Leiobunum and Hadrobunus. With regard to the near-basic position of Cyphophthalmi in currently proposed phylogenetic trees of Opiliones, naphthoquinones and ketones from Siro may represent the condition ancestral to the (derived) naphthoquinone- and ketone-rich secretions in phalangid Palpatores.  相似文献   
52.
Benzaldehyde, phenylacetaldehyde (major component), 2-phenylpropenal,n-heptanal, 6-methylhept-5-en-2-one, and linalool were identified as compounds responsible for the male scent ofAtrophaneura alcinous alcinous. These substances were present predominantly in the wings, and the quantity of them was largest at the inner margin of the hind wing. Female wings also contained some of them in much smaller (except a few components) amounts. The relative proportion of each component exhibited manifests sexual differences.  相似文献   
53.
Virgin females of the citrophilous mealybugPseudococcus calceolariae (Mask.) deposit scent marks as trails on the substrate on which they rest or move. These substances elicit attraction and sexual behavior by conspecific males. The same responses were obtained when males were bioassayed on extracts from filter paper disks on which females had rested. The significance of scent trailing in mealybugs is discussed.Homoptera, Coccoidea, Pseudococcidae.This work was supported by the Italian National Research Council (CNR).  相似文献   
54.
Adult captive European forest reindeer,Rangifer tarandus L., were exposed to hindfoot interdigital (ID) secretion placed on the ground. The animals were tested with blanks and interdigital secretion from themselves and male and female group members, and secretion from excised glands of male and female mountain reindeer. Responses to the stimuli consisted of sniffing, licking, and olfactory searching on the ground. With forest reindeer secretions, each sex responded more to its own ID secretion than to that of the opposite sex. Of the mountain reindeer samples, male ID secretion released stronger responses. The responses did not vary systematically from June to October. The functional significance of the ID secretion in free-ranging reindeer is discussed.  相似文献   
55.
Behavior observations in European reindeer (Rangifer tarandus) showed a high frequency of sniffing the tails of conspecifics. A caudal gland was found, and it is the largest skin gland inRangifer. Behavioral contexts of tail sniffing, the histology of the gland, and some aspects of the composition of the volatiles in the gland's secretion are described.  相似文献   
56.
以氧化亚硫酸化酯交换菜油为主要成分 ,与磺化动物油、磺化植物油和磺化矿物油等复合 ,再加入适量的香精 ,制成香味适宜的复合型皮革加脂剂 ,运用透射电子显微镜和激光衍射粒度分析仪等现代分析测试手段 ,研究了产品的组成、结构与性能之间的关系 ,试验结果表明 :所研制的香型复合加脂剂具有宜人、持久的香味 ,优良的应用性能。从理论上阐述了加脂剂组成、结构与应用性能之间的关系  相似文献   
57.
李维青 《酿酒科技》2003,(6):119-120
白酒变色主要原因是铁离子含量过高所致,但对人体健康无碍,反而有益,只是感官不易接受。因此,应采取适当措施控制白酒中的铁离子含量,以免其变色,影响感官质量。此外,高温发酵、酒海贮存、高粱原料都会不同程度使白酒带有淡黄色,与铁离子含量并无直接关系,应采取相应措施克服。  相似文献   
58.
[目的]鉴于荔枝蝽臭液的特性以及粮食储藏中害虫危害的严峻形势,采用三角瓶密闭熏蒸法探讨了荔枝蝽臭液对常见仓储害虫的熏蒸潜力。[结果]结果表明:荔枝蝽雄虫臭液24 h熏蒸毒力的LC50值分别为米象0.5247μL/L、谷蠧6.3125μL/L、四纹豆象2.4068μL/L、黄斑露尾甲3.7753μL/L;荔枝蝽雌虫臭液24 h熏蒸毒力的LC50值分别为米象0.4803μL/L、谷蠧6.3803μL/L、四纹豆象2.5936μL/L、黄斑露尾甲3.7925μL/L。[结论]荔枝蝽臭液对米象、谷蠧、四纹豆象和黄斑露尾甲等仓储害虫具有很好的熏蒸毒力,可望能从荔枝蝽臭液中筛选出有效的天然熏蒸化合物。  相似文献   
59.
张起贵  张妮 《电视技术》2014,38(3):169-172
为减少异常行为在公共场所造成的安全隐患,以复杂场景地铁为研究背景,从人工智能的角度出发,全面地分析异常行为特征并进行系统设计,快速标定视频监控场景。在上下文场景模型与异常行为模型建立的基础上,采用改进camshift算法对轨迹间断进行填补并跟踪,提出了一种以轨迹属性集对晕倒异常行为进行表征。实验结果表明,该算法能够快速分析地铁场景中的晕倒行为并及时预警,检测率为89.9%。  相似文献   
60.
Free-ranging muskrats were trapped in scented and blank traps in New York State at local ponds during all seasons and at a wildlife refuge in spring and early summer. In a total of 4839 trap-nights, 65 muskrats were caught. Trapping success was 1.34%. The overall responses to differently scented traps differed significantly. Adults preferentially entered blank and food-baited traps, whereas young showed no preference to blank, musk, or control odor. It appears that adults actively avoid musk, especially during the months May through July.  相似文献   
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