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排序方式: 共有3568条查询结果,搜索用时 15 毫秒
991.
为了在激烈的市场竞争中赢得竞争优势,很多国家和地区纷纷推出质量激励措施来激励和引导企业提高质量、提升竞争力.本文在研究国内外质量激励措施现状基础上,通过对比分析,提出了建设国家质量激励体系的建议. 相似文献
992.
Bian S Zhang Y Feng A Chiu L Wu S Hu Z 《Environmental monitoring and assessment》2008,138(1-3):281-287
This paper examines a small tidal system in Wanpingkou, Rizhao of China. The tidal system was originally maintained by a balance
of the natural interaction between tidal currents and waves. But this tidal system was diminishing by reclamation processes
since the 1980s, especially in 2003 when a sailing boat station was built in the study area. To investigate the stability
and development mechanism of the tidal system, its feasibility was evaluated before the sailing boat station was built. The
erosion and deposition in and out of the tidal system was analyzed, forecasted and compared with the data from field monitoring.
The results show that the tidal system would remain relatively stable, although its adjacent shoreline might change somewhat
after the newly built sailing boat station. This change would also affect the coastal water and wetland environment in the
study area. Further field monitoring in the area is still necessary. 相似文献
993.
The difference between fishermen's fishing catch and the optimal fishing catch is the basic reason for the transaction of marine fishing rights (TMFR). The effects of productive cost, non-productive cost, use-cost, transaction cost, productive revenue and non-productive revenue on the TMFR and the optimal fishing catch are analyzed. This paper draws following conclu- sions: the non-productive revenue has a positive effect on the TMFR, and other factors, such as non-productive cost, usecost and transaction cost, have a negative effect; the TMFR will promote the resource allocation; the high transaction cost may affect the implementation of TMFR. 相似文献
994.
活性炭纤维载体生物膜法处理洗车废水研究 总被引:2,自引:2,他引:0
为了实现洗车废水的循环使用,进行了以聚丙烯腈基活性炭纤维(PAN-ACF)为生物膜载体处理洗车废水的实验研究。以LAS、COD和NH3-N等指标考察了活性炭纤维生物膜反应器对洗车废水的处理效果。结果表明:在常温下、pH=6.5~7,当进水流量在30 mL/min时,反应器达到最佳运行参数,活性炭纤维载体生物膜法对LAS、COD和NH3-N等的去除率分别达到了97%、80%和60%。出水水质完全达到《生活杂用水水质标准》(CJ/T48-99)中洗车用水主要水质指标的规定。此外,实验表明PAN-ACF作为生物膜载体具有很好的生物亲和性和再生性。 相似文献
995.
996.
Robert M. Kahn Bruce D. Smith Austin Long 《Journal of the American Water Resources Association》1996,32(3):629-635
ABSTRACT: A study of 222Rn concentrations in the water distribution system of Tucson, Arizona, revealed levels of 60 to 1260 pCi/L in domestic waters. These measurements are comparable to levels of between 80 and 1400 pCi/l for 222Rn found in ground water samples in the North-Central Tucson basin (Kahn et al., 1994). Estimated loss of 222Rn due to radioactive decay during travel from the well head to the home ranges from 8 to 50 percent. 相似文献
997.
微生物传感器技术原理及其在水环境监测中的应用 总被引:1,自引:0,他引:1
微生物传感器技术产生于70年代,并且,已在水环境监测中得到应用,例如,BOD、NH3、NH4^+、NO2^-、NO3^-等项目分析;毒物测定和毒性评价;致突变物的筛选等。实践证明,该项技术具有快速、灵敏、易于自动控制、成本低廉等优点;可以相信,它必定会越来越多的应用于环境监测。 相似文献
998.
Roger B. Long 《Journal of the American Water Resources Association》1980,16(6):1002-1005
ABSTRACT: At a time in history when water resource development in the United States is being condemned as both economically inefficient and an environmental disaster, perhaps economists need to look back at previous development to see what the fruits of water development (be they sweet or sour) have been. The Boise Project of south-western Idaho is 70 years old and to some people it represents a gross error in resource use, while to others it represents a means of livelihood and well being. A recent research project at the University of Idaho attempted to measure not only the direct economic income benefits of the project (from irrigation), but also the indirect or secondary income benefits (from the food processing industry). Periodic regional input-output tables were constructed to assess the income generated from irrigation and food processing over the period from 1946 to 1970. Input-output analysis allowed researchers to evaluate the direct and indirect impacts of both the irrigation sector and the food processing sector and to compare their growth over time. 相似文献
999.
Effects of different forest management policies on long-term vegetation development are incorporated into a computer simulation of a western Washington watershed. The response of a Rocky Mountain elk(Cervus canadensis nelsoni) population to these vegetation changes is simulated using information on their differential use of vegetation types. Simulations include: 1) a cessation of timber harvesting leading to an immediate decline in elk members resulting from a reduction in summer habitats; 2) a stable elk population, similar to the present one, resulting from a constant timber harvesting rate, and 3) initial increases in herd size, followed within 50 years by a sharp decrease, resulting from cutting all old growth timber within the next decade and then a cessation of timber harvestings. 相似文献
1000.
资源条件对城市可持续发展的影响--以重庆市为例 总被引:4,自引:0,他引:4
根据城市发展对资源的依赖程度,把资源分为必需型资源和特色型资源两种类型,分别讨论了这两类资源对城市可持续发展的影响,然后在评价城市资源优劣势的基础上,提出了重庆市基于资源条件的持续发展对策. 相似文献