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排序方式: 共有712条查询结果,搜索用时 15 毫秒
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中国火灾科学的今天和明天 总被引:16,自引:3,他引:13
对我国火灾科学研究的现状和发展趋势进行了综述 ,介绍了火灾科学的兴起、我国火灾科学的发展以及火灾科学国家重点实验室的建立 ,并对我国火灾科学的未来进行了展望。 相似文献
626.
运动受限空间内火灾研究的现状与展望 总被引:1,自引:0,他引:1
从火灾科学基础研究的角度 ,提出了运动受限空间内火灾的概念。继而阐述了三种典型运动受限空间 (即运动着的航天舱、船舶、车辆 )内火灾研究的现状 ,并对未来运动受限空间内火灾的研究作了展望。还探讨了我国当前应开展的工作。 相似文献
627.
香港消防性能化设计的简略介绍 总被引:3,自引:1,他引:2
介绍了香港在消防工种领域性能化设计的应用和发展。简单地阐述了国际上的消防工程性能化设计的发展。概述目前的性能化设计现状并给出经验总结。 相似文献
628.
Simultaneous nitrification and denitrification in step feeding biological
nitrogen removal process 总被引:4,自引:1,他引:3
The simultaneous nitrification and denitrification in step-feeding biological nitrogen removal process were investigated under different influent substrate concentrations and aeration flow rates.Biological occunenee of simultaneous nitrification and denitrification was verified in the aspect of nitrogen mass balance and alkalinity.The experimental results also showed that there was a distinct linear relationship between simultaneous nitrification and denitrification and DO concentration under the conditions of low and high aeration flow rate.In each experimental run the floc sizes of activated sludge were also measured and the results showed that simultaneous nitrification and denitriflcation could occur with very small size of floc. 相似文献
629.
Richard J. Vogl 《Environmental management》1979,3(1):51-57
Fire management of grasslands is best executed based on an understanding of the fundamental properties of grassland components, structures, and environments, and the nature of fire behavior in grassland fuels. The art of controlled burning combines experience, practicality, empirical knowledge, and sensitivity, with the effects of fire, the role of fire (particularly under natural conditions), inherent climatic conditions, and sound ecological management objectives. Some of the properties, effects, roles, conditions, experiences, and objectives of grassland burning are presented. 相似文献
630.
In several species of ants, queens often form temporary cooperative associations during colony foundation. These associations
end soon after the eclosion of the first workers with the death or expulsion of all but one of the queens. This study examined
competition between foundress queens of the fire ant Solenopsis invicta. Although attacks by the workers contributed to queen mortality, queens gained no advantage by producing more workers than
their co-foundresses. Restriction fragment length polymorphism analysis of mitochondrial DNA showed that the queen producing
more workers during colony founding was no more likely to survive than the less productive queen. In experimentally manipulated
colonies in which all the workers were daughters of only one of the queens, the mother of the workers was no more likely to
survive than the unrelated queen. Queens producing diploid males reared fewer offspring but were as likely to survive as queens
producing only workers. These results suggest that workers do not discriminate between related and unrelated queens within
colonies. Aggressive encounters between queens were common. Queens were more likely to die or be expelled if paired with heavier
queens or if they lost more weight than their co-foundress during the claustral period. Finally, when queens were separated
by screens through which workers could pass, the workers usually attacked and killed the queen farther from the brood. These
results suggest that queen survival is promoted by a high fighting ability relative to co-foundresses, rather than by increased
worker production, and that workers respond to queen differences that are independent of kinship.
Received: 8 September 1995/Accepted after revision: 5 March 1996 相似文献