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51.
Published:// 《中国标准化(英文版)》2007,24(6):10-13
There are no explicit laws concerning food recalls in China; moreover, some related regulations have weaknesses. China should first create a system of laws and regulations governing food recalls, establish a system to recall defective food, and strengthen administrative and legal remedial mechanisms related to consumer rights. 相似文献
52.
根据保护煤柱设计原理 ,利用微机采用垂线法留设保护煤柱的数学模型、程序流程以及得到的算例结果。利用该方法 ,只要将有关资料输入计算机 ,就能快速准确地自动计算出煤柱角点坐标、煤柱面积和压煤量。 相似文献
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介绍了武钢热轧厂烟气中残氧量自动监测技术及燃烧工艺试验 ,评述该项技术研究动态 ,指出它对节能降耗和环境保护的作用 相似文献
56.
Exposure to turbulence, an environmental stimulus, produces behavioral adaptation in the Aplysia siphon-withdrawal response (SWR). The authors show that the duration and spatial extent of turbulence influence adaptation recovery. In terms of duration, recovery in whole animals and reduced preparations (tail, siphon, and CNS) was more rapid after longer exposures to turbulence (10 min) than after briefer exposures (10 s-5 min). In terms of spatial extent, recovery in reduced preparations was more rapid after diffuse turbulence (tail and siphon together) compared with focal turbulence (siphon alone). Furthermore, spatial extent and duration interact: Duration regulates recovery only when turbulence is diffuse. Results suggest that SWR adaptation reflects a composite of cellular processes, including short-term synaptic enhancement in L30 inhibitory interneurons. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Capital cost correlations are given for oil-water separators, equalization basins, primary clarifiers, clarifiers and clarifier mechanisms, reverse osmosis unit, ultrafiltration units, gravity filters and miroscreens. Data are included for raw sewage, intermediate and recirculation pumping stations and for preliminary treatment (or bar screens, grit removal, overflow and bypass chamber and Parshall flume), for grit removal, comminution and gas stripping. The correlations are accurate to ± 30%, expressed in Canadian dollars and adjusted to a Marshall and Swift value of 1000. Details as to what components are included in the cost are given. Data are given for the labour and material costs to create a working process module. For inflation indices, a critique of the Engineering News Record, EPA small city, Marshall and Swift, Chemical Engineering and Southam inflation indices suggested that the Marshall and Swift index is most appropriate for the construction and process equipment studied here. Concerning the currency exchange, for the equipment and processes in this study, equipment costs the same whether expressed directly in US or Canadian dollars. To put the current data into perspective, several hundred sources of cost data were analyzed. The major correlations are compared, on a consistent basis, with current data. 相似文献
58.
Environmental Effects of Hydro-Electric Power Generation in Africa and the Potential for Artificial Floods 总被引:1,自引:0,他引:1
Electricity is a fundamental requirement for economic growth, and hydro-electric power is often thought to be environmentally benign. However, the construction and operation of many hydro-power dams in Africa have had significant negative impacts on the environment and rural economies. Reduced downstream flooding has destroyed fisheries and starved the floodplain soils of moisture and nutrients. Often the worst-affected areas have no electrification and therefore do not benefit from power generation. New dams which are planned in Kenya and Tanzania have been specifically designed to make flood releases. This will allow electricity to be generated whilst maintaining a dynamic flooding pattern for the short-term economic importance of fisheries and agriculture and the longer-term importance of soil fertility and biodiversity. Involvement of local community representatives in deciding when flood waters should be released on the Phongolo River in South Africa has resulted in substantial benefits to floodplain users. 相似文献
59.
J. Schanda 《Color research and application》2007,32(3):233-235
This is a comment to the editorial by J. Hutchings on “Talking about Color… and Ethics.” © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 233–235, 2007 相似文献
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