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281.
分析了离子膜制碱生产过程中电解槽氢气泄漏的原因,提出了应急处置方法和预防控制措施.  相似文献   
282.
浅析生态厕所在旅游业中的发展应用   总被引:1,自引:0,他引:1  
鉴于水资源日益短缺,自然环境脆弱的实际情况,同时为了突破制约旅游业发展的"旅游厕所"这一瓶颈,坚持使用高科技、节能环保的生态厕所技术,以确保旅游业持续、快速、健康的发展.由于并非每一种生态环保厕所技术都适用于旅游业.文章从对现有的生态厕所进行技术归类、分析、总结,提出了适应于旅游业发展的生态厕所技术类型以及适用场所,并进一步指出现有生态厕所在应用中存在的一些技术问题.  相似文献   
283.
文章对鞍山市环境空气中细颗粒物(PM2.5)、可吸入颗粒物(PM10)季节性变化及月变化污染特征进行分析,不同季节的PM2.5、PM10变化趋势均为夏季〈秋季〈春季〈冬季;PM2.5、PM10的月均质量浓度按高低顺序分别为:12月〉1月〉11月〉2月〉10月〉4月〉3月〉7月〉8月〉6月〉5月〉9月和1月〉12月〉3月〉4月〉2月〉10月〉11月〉5月〉6月〉7月〉8月〉9月。同时,分析了ρ(PM2.5)对ρ(PM10)的贡献率,全年的ρ(PM2.5)/ρ(PM10)平均值为57.8%,结果表明,在PM10中,PM2.5的含量要大于PM2.5-10的含量。  相似文献   
284.
This study aims to identify effective antialgal allelochemicals from marine macroalgae that inhibit the growth of red tide microalgae. Practically, new algicidal agents were developed to control red tide. The growth inhibitory effects of 5 marine macroalgae Porphyra tenera, Laminaria japonica, Ulva pertusa, Enteromorpha clathrata, and Undaria pinnatifida on Skeletonema costatum were evaluated by adding crude seawater extracts of macroalgal dry tissue into the culture medium containing S. costatum. The half-effective concentrations at 120 h (EC50, 120 h) of the seawater extracts were 0.6, 0.9, 1.0, 1.0, and 4.7 g/L for the five macroalgae above, respectively. E. clathrata, L. japonica and U. pertusa showed strong allelopathic effect on the growth of S. costatum. There have been no previous reports with regard to the allelopathic effects of the former two macroalgae so far. The possible allelochemicals of 21 compounds of the E. clathrata were detected using Gas chromatography-mass spectrometry (GC-MS) analysis. Unsaturated fatty acids, acrylic acid (C3H4O2), and linolenic acid (C18H30O2) were the most likely allelochemicals in E. clathrata.  相似文献   
285.
目前国内外针对水利设施遭受冰冻灾害的研究还很不活跃,获得的成果还不系统。本文系统分析总结2008年我国南方遭受罕见雪灾导致水利设施的损害情况,以及这些水利设施在极端冰灾影响下的破坏形式,进而提出了一系列有关南方水利设施遭遇极端雪灾的对策,以适应将来积极防灾减灾的需要。  相似文献   
286.
经过几年的努力,我国自然灾害应急机制的建设取得了很大的成绩,但2008年伊始的一场冰雪灾害却暴露了我国自然灾害应急机制存在的诸多问题。因此,必须从灾害预警、灾害信息公布、灾害自救、应对突发事件的组织体制和有关应急预案、法律法规的落实等方面对我国自然灾害应急机制加以完善。  相似文献   
287.
本文介绍了挥发性有机废气的生物处理方法和技术应用,对在国内外应用较广的吸附法、热破坏法、冷凝法、生物法进行了阐述,通过和其它废气处理工艺进行的经济技术对比,表明了生物处理工艺在其适用范围内的优越性.  相似文献   
288.
Abstract

Nowa days, ecological and cultural tourism, especially those ancient villages and towns in China, have attracted an increasing number of tourists because of their unique cultural features. However, rapid development of tourism brings economic benefits, but results in a series of problems that threaten further tourism development and protection of ancient towns, such as over-commercialization and tourism urbanization. Taking Longmen ancient town as an example, this paper presented a sustainable way of preserving and developing resources of ancient villages and towns. First, identify cultural features and the extent of ancient villages and towns, and find the approach through which a cultural landscape zoning can be applied. Second, define a cooperative function area to release the pressure on core areas and protect their authentic cultures by extending tourism space. Third, balance tourism development with traditional industries to enhance the sustainability of community economies.  相似文献   
289.
Abstract

Nowadays the rising of opportunity cost of farm labor comes to the forefront of attention in China. In order to understand its impact on agricultural land-use structure, a theoretical framework of household economics is formulated drawn on Low’s model. Under the theoretical framework, the impact of the rising opportunity cost of on-farm on cropping structure is deduced in theory. And then, using statistic and survey data, taking mountain area of southern Ningxia as an example, the theoretical assumes are verified. The results show that the rise of opportunity cost of farm labor leads to less diversified cropping structure.  相似文献   
290.
In 1999 China adopted the "Conversion of Cropland to Forest and Grassland Program" (CCFGP), a nationwide ecological recovery program, to minimize wide-scale soil erosion and vegetation degradation in China, as well as to improve water budgeting results. In the 10 yr since implementation, the CCFGP has resulted in the recovery and reforestation of >100,000 km of cropland and bare land, though the quantitative effect of this program on catchment water budget is not entirely clear. Therefore, we used the Soil and Water Assessment Tool to evaluate and quantify the effects of the CCFGP on the water budget of the Jinghe River catchment, a tributary of the Yellow River covering the central region of the Loess Plateau. Our results indicated that precipitation had dropped by 12.0% from the 1970s (611.6 mm) to the 2000s (538 mm) and that there was a corresponding 25.2% decrease in humidity index from 0.48 to 0.36. Before the CCFGP's implementation, forest and grassland had been decreasing, while bare land, cropland, and shrub land had been increasing. After the implementation of the CCFGP, the opposite trend was observed. Moreover, streamflow increased by about 15 and 20% for the upstream and middle stream subbasins, respectively, while soil water content also showed an obvious increase. Over the same period, evapotranspiration decreased by 5.2 and 13.5 mm and runoff decreased by 37.5 and 38.6% in the two subbasins. The same trends were obtained in the downstream subbasin, where changes were even greater. As a result of the reduced runoff and evapotranspiration, utilization of water resources was more efficient and ecological environment was improved under the CCFGP policy. Our results indicate the CCFGP resulted in a favorable ecological impact and should therefore be maintained.  相似文献   
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