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61.
Many lizards are capable of identifying food using only chemical cues from food surfaces, but almost nothing is known about the types of compounds that are effective stimuli. We experimentally studied lingual and biting responses by a lacertid lizard, Podarcis lilfordi, to single representatives of three major categories of food chemicals, sucrose as a carbohydrate, pure pork fat as a mixture of lipids, and bovine gamma globulin as a protein. In 60-sec trials in which stimuli were presented on cotton swabs, the lizards detected all three stimuli, exhibiting more tongue-flicks, licks, or bites, or a greater tongue-flick attack score (TFAS; overall measure of response strength to prey stimuli) than to deionized water. The initial response to all stimuli was tongue-flicking, but the lizards discriminated among the types of chemical stimuli. After preliminary tongue-flicks, the lizards responded to sucrose solutions by licking at high rates, to pure pork fat by biting, and to protein by a combination of additional tongue-flicks and biting. Biting is a feeding response to prey or solid plant material. Licking is a feeding response to sugars in nectar or ripe fruit. Its frequency increased with sucrose concentration. Our data suggest that lizards can identify several types of chemicals associated with food and direct feeding attempts to sources of such chemicals in the absence of visual cues. 相似文献
62.
天然气(CH4)转化制得CO+H2合成气可以生产氨、甲醇及有机化工产品,需要按照转化原理进行工艺优化,以节省原料消耗,满足合成产品对组分要求. 相似文献
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合成香料特别是酯类合成香料是食品工业、化妆品和制药工业的重要原料。这里介绍了近十年来酯类合成香料在研究开发和工艺改进方面的进展情况,为今后酯类合成香料的发展提供了宝贵的参考价值。 相似文献
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通过对沸石滤柱吸附去除饮用水中微量邻苯二甲酸酯(又称为酞酸酯,phthalate esters,PAEs)的研究,探讨其工程应用的可行性.邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二辛酯(DOP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)4种PAEs被选作目标物质.控制沸石滤柱的空床接触时间为12~18 min,使DMP、DBP、DOP及DEHP 4种酯类进水浓度皆为20~100μg/L;通过高效液相色谱法(HPLC)测定出水中每种PAE的浓度.研究发现,总PAEs的去除率在24.7%~33.8%之间;随着进水浓度的增加,DMP、DBP的去除率下降,DEHP、DOP去除率上升. 相似文献
67.
危险化学品突发泄漏事故应急决策系统研究 总被引:2,自引:0,他引:2
针对危险化学品突发泄漏事故需要应急反应,通过建立危险化学品及其特性数据库,利用GIS技术,实现地图数据的动态装载,实现一个面向危险化学品突发泄漏事故的应急决策系统.该系统可以向危险化学品相关行业人员提供相关化学品的理化性质,生产、运输所需的工具、操作方法和步骤,实现数据的双向更新,做到对危险化学品的实时监控,并在发生突发泄漏事故时软件能够及时自动生成紧急处置预案,包括处置方法、手段和标准.在突发泄漏事故发生时为领导决策层提供科学依据,实现快速反应,防止重大事故的发生. 相似文献
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In order to study the movement characteristics of groundwater in a deep mining area and solve the dispute of the distri-bution rule of hydro-chemical zoning which is contradicted by lixiviation water zoning in a horizontal direction, we directed our attention to the source of deep groundwater, its seepage and hydro-chemical characteristics in a typical mining area. We used a neotectonic water-control theory, chemical and isotope methods, as well as a method for analyzing dynamic groundwater conditions. The results indicate that 1) Karst water in the deep and medium parts of this mining area is recharged by vertical leakage through neotectonic fractures rather than seepage along strata from subcrop parts or surrounding flows; 2) from surface to deep leakage paths, the variation in the types of chemical groundwater agrees with the normal lixiviation water distribution rule and the age of mixed groundwater increases; 3) the water-rich zones along neotectonic fractures correspond with water-diluted zones in a hori-zontal direction; 4) the leakage coefficient and water capacity of aquifers increases during the flow process of Kant water along the antidip direction (from west to east) and 5) Karst water in shallow mining areas forms a strong runoff belt along strikes and quickly dilutes the water from deep and medium mining areas. Overall, chemical and dynamic water characteristics actually agree with in terms of the entire consideration for differences in vertical leakage and abnormalities in the zone of water chemical distribution, along a horizontal runoff direction. 相似文献
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