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61.
刘亚军 《数码设计:surface》2014,(8):102-104
广告机这一产品通过视频、音频的形式向公众传达信息,其主要使用环境为公共场合。在广告机概念设计上。不仅注重外观的时尚和简洁,有时为了向人们传达环保的理念,特别在广告机面板下方的广告单领取口镂空丝印一个树和海洋图标。当人们领取广告单时,广告单数量减少.图标会逐渐的产生变化。通过这种图标的变化来警示人们环保的重要性。 相似文献
62.
Walking tracks of Colorado potato beetles,Leptinotarsa decemlineata Say, were recorded on a locomotion-compensator in response to wind, odors of host plantsSolanum tuberosum L. and nonhost plantsLycopersicon hirsutum f.glabratum C.H. Mull, and to mixtures of these plant species. Host-plant odor induced positive anemotactic responses in starved females, whereas odor of the nonhostL. hirsutum was neither repellent nor attractive. The attractiveness of host-plant odor, however, was neutralized in the odor blend of plant species. Masking the attractive host-plant odor will hinder the beetle's searching for host-plant patches, and this principle may be exploited in pest control by mixed cropping.The locomotion-compensator was constructed with financial support from the Foundation for Fundamental Biological Research (BION), which is subsidized by the Netherlands Organization for the Advancement of Pure Research (ZWO), grant 14-02-02. The first author was supported by a grant from the French Ministry of Industry and Research. 相似文献
63.
研究试验温度和停放时间对胶料加工性能的影响。结果表明,试验温度对胶料的门尼粘度、门尼焦烧时间和硫化特性均有一定影响。门尼粘度测定的试验温度选择100℃;门尼焦烧时间测定的试验温度一般选120℃,SBR胶料可提高至130℃左右,以缩短试验时间;硫化特性测定的试验温度一般选185℃。试验前模腔达到规定温度后再保持15min,以使转子与模腔温度一致。胶料停放时间应控制在2h左右。 相似文献
64.
Two monophagous sawflies,Neodiprion dubiosus andN. rugifrons, actively avoid feeding on the current season's needles of jack pine,Pinus banksiana, while the polyphagousN. lecontei feeds indiscriminately on foliage of all age classes. Bioassay studies with needle extracts indicate thatN. dubiosus andN. rugifrons larval feeding preference is governed by a group of tricyclic diterpene resin acids. Resin acids commonly occur in needles of all ages; however, levopimaric, palustric, dehydroabietic, and neoabietic acids were at higher concentrations in the new needles.N. dubiosus was significantly deterred from feeding on 1-year-old foliage when treated with the pure resin acids, palustric and levopimaric, at 0.5 and 1.0 mg/ml MeOH.N. rugifrons larvae were deterred from feeding by pure dehydroabietic, neoabietic, and palustric acids at 1.0 mg/ml MeOH. 相似文献
65.
影视动画产业是当今社会的朝阳产业,是传统经济发展和延伸的一种新方式,政府对影视动画产业十分重视.而影视文化产业具有浓厚文化色彩和广阔的自由发展空间,有利于影视动画的进一步发展与建设.影视动画产业发展对象可以是影视基地,也可以是影视剧本,产业发展对象丰富,所以此产业的发展前景非常明朗,并且还具有高度的研究价值. 相似文献
66.
油水乳化液流变性研究进展 总被引:8,自引:0,他引:8
综述了油水乳化液流变性研究进展,介绍了目前国内外乳化液流变性的研究情况、乳化液的流变模式及乳化液流变性的评价方法。乳化液的剪切应力-剪切速率关系明显受油滴尺寸的影响,在含油量一定时,表观黏度随油滴尺寸的减小而增加。绝大多数乳化液在低剪切速度下(低于50s^-1),呈现剪切变稀行为;在剪切速率超过1000s^-1时呈现牛顿行为。高含水原油的视黏度是温度、含水率以及剪切速率的函数。介绍了乳化液的3种流变模式,并给出了流变性评价方法实例。提出了油水乳化液流变性研究的发展方向。 相似文献
67.
Vickers NJ 《Journal of chemical ecology》2002,28(6):1255-1267
Heliothis subflexa males were flown in a wind tunnel to a variety of combinations of synthetic pheromone components admixed on a filter paper disk. Blends containing (Z)-11-hexadecenal (Z11–16:Ald, 1000 ng), (Z)-9-hexadecenal (Z9–16:Ald, 500 ng) and (Z)-11-hexadecenol (Z11–16:OH, 10–500 ng) elicited upwind flight and source contact in 52–69% of males. All these compounds have previously been isolated and identified from female H. subflexa gland extracts and volatile pheromone emissions. Males were not attracted by blends in which Z9–16:Ald was omitted (0% source contact). Similarly, blends lacking Z11–16:OH were unattractive to male H. subflexa (3% or less source contact). Males were extremely sensitive to the presence of Z11–16:OH; however, responding in high numbers (57–69% source contact) to blends containing a dosage of 1% (10 ng) or greater Z11–16:OH. Males were unresponsive to blends in which Z9–16:Ald was replaced with a variety of dosages of (Z)-9-tetradecenal, a secondary component of a closely-related congeneric species, Heliothis virescens. Another compound present in the blend emitted by conspecific females, (Z)-11-hexadecenyl acetate (Z11–16:Ac), did not inhibit H. subflexa males (69% source contact) when added to the three-component mixture (1:0.5:0.1) at a ratio of 0.1 (100 ng) with respect to Z11–16:Ald. These results indicate that Z9–16:Ald and Z11–16:OH are required in addition to Z11–16:Ald to elicit significant levels of upwind flight in H. subflexa males. The effects of Z11–16:Ac are more subtle, but at the dosage tested in these experiments, this compound does not have an antagonistic effect on upwind flight and source location by H. subflexa males. 相似文献
68.
The responses of the striped ambrosia beetle,Trypodendron lineatum (Olivier) (Coleoptera: Scolytidae), to modified drainpipe traps baited with the host attractant ethanol, the aggregation pheromone lineatin, both alone and in combination, were studied in a wind tunnel. Exposure of males to ethanol increased their frequency of steady, upwind flight; however, only lineatin was effective in inducing them to land on and enter the traps. In contrast, exposure of females to either ethanol or lineatin alone resulted in an increased frequency of trap landing and entry. Both compounds released simultaneously did not significantly increase the frequency of trap landing and entry for either sex. These responses are consistent with the life history strategies used by both sexes to seek and colonize suitable host material. 相似文献
69.
梁端翼缘扩大型梁柱节点抗震性能和设计方法 总被引:1,自引:0,他引:1
为使钢框架梁柱节点满足强柱弱梁的抗震设计原则,并使梁上塑性铰远离梁柱节点区,对梁端翼缘扩大型(包括侧板加强型和翼缘端部放大型)钢框架梁柱节点进行了往复荷载下的试验研究,得到了节点类型和梁端翼缘扩大尺寸对节点滞回性能、延性和耗能能力等指标的影响规律.在使用非线性有限元程序对试验结果进行数值模拟的基础上,研究了梁端翼缘扩大段的长度及宽度等参数对节点性能的影响规律和有效取值范围,给出了实用设计方法.使用梁端翼缘扩大型钢框架节点可以有效实现梁端塑性铰外移,是一种在抗震设计中值得推广的具有良好延性和塑性转动能力的新型节点形式. 相似文献
70.
型钢翼缘狗骨式削弱在型钢混凝土节点的作用 总被引:1,自引:0,他引:1
为了防止地震时型钢混凝土节点核心区发生剪切破坏以及梁柱连接焊缝发生脆性断裂,提出对型钢混凝土节点核心区附近梁端型钢的上、下翼缘采取狗骨式削弱,并系统研究翼缘削弱对提高型钢混凝土节点抗震性能的作用.研究表明,由于在梁端型钢翼缘采取狗骨式削弱,不仅能够将塑性铰控制在梁型钢削弱的位置,从而有效地降低了节点核心区所受的剪力以及梁柱连接焊缝的应力;而且能够改善节点塑性铰区的转动能力和抗剪性能,提高节点的延性和耗能能力. 相似文献