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421.
活性炭纤维吸附—催化燃烧新装置处理有机废气 总被引:1,自引:0,他引:1
介绍了一种处理有机废气的吸附一催化燃烧新型装置,以活性炭纤维为吸附剂,结合多单元分流组合式吸附床,采用PLC电脑来实现整个系统的连续运行,实际运行结果表明,对于处理大风量、低浓度的有机废气,该技术与其它技术相比具有净化效率高、节能降耗、自动化水平高等优点。 相似文献
422.
新银盐光度法测定废水中的砷 总被引:2,自引:0,他引:2
通过改变测定吸收波长和降低试剂空白值,提高了样品测定的准确度和精密度. 相似文献
423.
论"绿色GDP"核算体系及其面临的问题 总被引:6,自引:0,他引:6
阐述了"绿色GDP"理论的形成与发展,结合中国国情,探讨了"绿色GDP"核算体系,进而分析了当前中国实现"绿色GDP"核算所面临的主要问题,提出了实现"绿色GDP"核算的主要对策和措施.从而让人们放弃传统的经济发展模式,采用循环经济发展模式,走新型工业化道路. 相似文献
424.
常规废水生物处理方法优缺点比较及生物处理技术新进展 总被引:7,自引:0,他引:7
对目前常用的废水生物处理方法的优缺点作了简要的总结、比较。介绍了微生物在废水处理中的一些特殊作用及一些新的生物处理技术。 相似文献
425.
426.
对溧水神仙洞的发掘和进行地质、地貌、孢粉、古脊椎动物与古人类、C14 年代及考古等多学科综合研究结果表明 :该洞是石炭系石灰岩沿层面裂隙经地下水溶蚀而成 ;洞穴堆积物的时代应属全新世早期 ,或新石器时代早期 ,绝对年代距今约为 1.1万年。其中发现的动物群为我国南方晚更新世动物群向现代动物群过渡的类型 ,而代表中 -晚更新世的最后鬣狗与代表新石器时代文化标志的陶片共生 ,为我国第四纪时代的划分 ,或新、旧石器时代文化的划分提供了重要依据。陶片则迄今为止是我国具有完整地层层位记录的最古陶片。它的发现 ,不仅将我国新石器时代文化大大推前 ,更为重写中华古史 ,校正“中华五千年文明”的提法 ,将中华文明追溯到一万年前并重排世界古文明位次增加了依据。同时 ,智人颞骨的发现 ,对长江中、下游古人类的研究 ,也提供了新的资料 相似文献
427.
The bioeconomic analysis of endangered species without consumptive values can be problematic when analysed with density-dependent models that assume a fixed environment size. Most bioeconomic models use harvest as a control variable, yet when modelling non-harvestable species, frequently the only variable under control of conservationists is the quantity of habitat to be made available. The authors explore the implications of this in a model developed to analyse the potential population recovery of New Zealand’s yellow-eyed penguin. The penguin faces severe competition with man for the terrestrial resources required for breeding and has declined in population to perilously low levels. The model was developed to estimate the land use required for recovery and preservation of the species and to compare the results to current tourism-driven conservation efforts. It is demonstrated that land may serve as a useful control variable in bioeconomic models and that such a model may be useful for determining whether sufficient incentives exist to preserve a species. However, the model may generate less useful results for providing a specific estimate of the optimal allocation of land to such a species. 相似文献
428.
Abstract: Customary forms of resource management, such as taboos, have received considerable attention as a potential basis for conservation initiatives in the Indo-Pacific. Yet little is known about how socioeconomic factors influence the ability of communities to use customary management practices and whether socioeconomic transformations within communities will weaken conservation initiatives with a customary foundation. We used a comparative approach to examine how socioeconomic factors may influence whether communities use customary fisheries management in Papua New Guinea. We examined levels of material wealth (modernization), dependence on marine resources, population, and distance to market in 15 coastal communities. We compared these socioeconomic conditions in 5 communities that used a customary method of closing their fishing ground with 10 communities that did not use this type of management. There were apparent threshold levels of dependence on marine resources, modernization, distance to markets (<16.5 km), and population (>600 people) beyond which communities did not use customary fisheries closures. Nevertheless, economic inequality, rather than mean modernization levels seemed to influence the use of closures. Our results suggest that customary management institutions are not resilient to factors such as population growth and economic modernization. If customary management is to be used as a basis for modern conservation initiatives, cross-scale institutional arrangements such as networks and bridging organizations may be required to help filter the impacts of socioeconomic transformations. 相似文献
429.
A review of wetland impacts authorized under the New Jersey Freshwater Wetlands Protection Act (FWPA) was conducted based on permitting data compiled for the period 1 July 1988 to 31 December 1993. Data regarding the acreage of wetlands impacted, location of impacts by drainage basin and watershed, and mitigation were analyzed. Wetland impacts authorized and mitigation under New Jersey's program were evaluated and compared with Section 404 information available for New Jersey and other regions of the United States.Under the FWPA, 3003 permits were issued authorizing impacts to 234.76 ha (602.27 acres) of wetlands and waters. Compensatory mitigation requirements for impacts associated with individual permits required the creation of 69.20 ha. (171.00 acres), and restoration of 16.49 ha (40.75 acres) of wetlands. Cumulative impacts by watershed were directly related to levels of development and population growth.The FWPA has resulted in an estimated 67% reduction [44.32 ha (109.47 acres) vs 136.26 ha (336.56 acres)] in annual wetland and water impacts when compared with Section 404 data for New Jersey. For mitigation, the slight increase in wetland acreage over acreage impacted is largely consistent with Section 404 data.Based on this evaluation, the FWPA has succeeded in reducing the level of wetland impacts in New Jersey. However, despite stringent regulation of activities in and around wetlands, New Jersey continues to experience approximately 32 ha (79 acres) of unmitigated wetland impacts annually. Our results suggest that additional efforts focusing on minimizing wetland impacts and increasing wetlands creation are needed to attain a goal of no net loss of freshwater wetlands. 相似文献
430.
Peter N. Swift 《Environmental management》1993,17(1):83-97
The United States Department of Energy is developing the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico for
the disposal of transuranic wastes generated by defense programs. Because changes in climate during the next 10,000 years
(10 ka) may affect performance of the repository, an understanding of long-term climate variability is essential for evaluating
regulatory compliance.
Fluctuations in global climate corresponding to glaciation and deglaciation of the northern hemisphere have been regular in
both frequency and amplitude for at least 780 ka. Coolest and wettest conditions in the past have occurred at the WIPP during
glacial maxima, when the North American ice sheet reached its southern limit roughly 1200 km north of the WIPP and deflected
the jet stream southward. Average precipitation in southeastern New Mexico during the last glacial maximum 22-18 ka before
present (BP) was approximately twice that of the present. Driest conditions (precipitation approximately 90% of present) occurred
6.5-4.5 ka BP, after the ice sheet had retreated to its present location. Wet periods of unknown duration have occurred since
the retreat of the ice sheet, but none have exceeded glacial conditions. Global climate models suggest that anthropogenic
climate changes (i.e., warming caused by an increased greenhouse effect) will not result in an increase in precipitation at
the WIPP. The climate of the last glacial maximum is therefore suitable for use as a cooler and wetter limit for variability
during the next 10 ka. 相似文献