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71.
为了提高实际污水处理工艺中除磷效率,优化系统中厌氧释磷的条件,主要研究了三种不同原水投加方式对厌氧释磷过程的影响。本试验采用UniFed SBR系统内的活性污泥,考察了实际生活污水对活性污泥的释磷影响,采用1次进水、4次进水和连续进水3种不同原水供给方式对于厌氧释磷性能进行比较。研究结果表明,不同进水方式可有效延长实际生活污水的注入时间,大大提高其中有机底物的可利用性,释磷速率由0.082增至0.143 mg/(L.min),其中单位活性污泥释磷量分别为2.24×10-3、3.26×10-3和3.80×10-3mg/mg,这种碳源投加方式的改变,使得利用实际生活污水的厌氧释磷特性得到优化,并提高了实际生活污水中有机碳源的可利用性和除磷效率。  相似文献   
72.
Introduction: Currently, risky driving behaviour is a major contributor to road crashes and as a result, wide array of tools have been developed in order to record and improve driving behaviour. Within that group of tools, interventions have been indicated to significantly enhance driving behaviour and road safety. This study critically reviews monitoring technologies that provide post-trip interventions, such as retrospective visual feedback, gamification, rewards or penalties, in order to inform an appropriate driver mentoring strategy delivered after each trip. Method: The work presented here is part of the European Commission H2020 i-DREAMS project. The reviewed platform characteristics were obtained through commercially available solutions as well as a comprehensive literature search in popular scientific databases, such as Scopus and Google Scholar. Focus was given on state-of-the-art-technologies for post-trip interventions utilized in four different transport modes (i.e. car, truck, bus and rail) associated with risk prevention and mitigation. Results: The synthesized results revealed that smartphone applications and web-based platforms are the most accepted, frequently and easiest to use tools in cars, buses and trucks across all papers considered, while limited evidence of post-trip interventions in -rail was found. The majority of smartphone applications detected mobile phone use and harsh events and provided individual performance scores, while in-vehicle systems provided delayed visual reports through a web-based platform. Conclusions: Gamification and appropriate rewards appeared to be effective solutions, as it was found that they keep drivers motivated in improving their driving skills, but it was clear that these cannot be performed in isolation and a combination with other strategies (i.e. driver coaching and support) might be beneficial. Nevertheless, as there is no holistic and cross-modal post-trip intervention solution developed in real-world environments, challenges associated with post-trip feedback provision and suggestions on practical implementation are also provided.  相似文献   
73.
This paper explores whether ambitions to open up the traditional Swedish model of top-down conservation methods to local influences are indicative of an actual transition in governance of Swedish national park policy (NPP), and examines whether such a shift entails an increase in local influence over local interests and needs. Methodologically, we analyse a combination of governance types and incorporate theoretical definitions of power and accountability. The establishment of new governance arrangements – where power is shared, interactions promoted and accountability is directed downwards – indicates that Sweden's NPP is undergoing a change in its mode of governance. This change also seems to include ceding some influence to local interests, and the possibility of combining conservation with the utilisation of certain natural resources. The results of our research also provide valuable insights into when the establishment of shared-governance arrangements are likely to succeed; in short, this seems more likely when there are established sectors sited in a robust legal framework and where strong international commitments potentially play a role. In conclusion, we contend that when seeking diversified governance arrangements it is not enough simply to take local practices and customs into consideration – they have to be strengthened.  相似文献   
74.
基于资源比较优势的森林公园旅游增长方式合理性研究   总被引:1,自引:0,他引:1  
利用Cobb-Douglas函数对各省森林公园旅游增长方式进行判别,结合“资源比较优势”和“资源利用合理度”,重点分析旅游资源在森林公园旅游增长过程中的作用及其利用水平。研究发现:中国森林公园在旅游增长过程中,不仅存在资本投入过剩现象,也存在旅游资源利用不合理的现象,并且由于资本投入过剩直接导致部分省份的旅游资源处于不合理利用状态,表现为旅游资源“利用过度”和“利用不足”;全国有19个省份的旅游资源利用状态处于不合理状态,其中8个处于过度开发状态,以东部沿海和中部省份为主;11个处于利用不足状态,以西南和西北各省为主。旅游资源禀赋、旅游资源比较优势和旅游资源利用合理度会因各省资本投入的不同而出现不完全匹配的发展局面。  相似文献   
75.
煤矿区生态修复过程中不可避免地改变了土壤水和溶质运移过程.土壤水是溶质运移的主要载体,溶质运移受土壤水文性质与植被状况影响.以我国北方典型半干旱区山西古交矿区草本、灌草和乔灌草3种不同生态修复区和撂荒地的土壤为研究对象,揭示不同生态修复模式下土壤水文性质变化规律及其对溶质运移的影响.结果表明,土壤持水性从大到小依次为乔灌草地灌草地草地撂荒地,草本、灌草和乔灌草3种植被修复区的土壤持水量相对于撂荒地分别增加了33.79%、59.19%和62.71%,植被修复有助于增加土壤层蓄水能力.土壤饱和导水率由大到小依次为草地(1.736 mm·min~(-1))灌草地(1.678 mm·min~(-1))乔灌草地(1.564 mm·min~(-1))撂荒地(1.012 mm·min~(-1)),非饱和导水率随吸力增大而呈指数下降,植被修复过程中降低容重的同时提高了土壤持水性,改善土壤持水性能.不同生态修复区土壤中溶质穿透时间呈草地灌草地乔灌草地撂荒地的趋势.CDE、SC和TRM模型均可对矿区不同生态修复模式土壤的溶质运移过程进行较好的表达,其中CDE模型拟合效果最好.结果表明研究区溶质运移方式以对流为主,而且土壤容重和砂粒含量是影响溶质运移的主要因素.  相似文献   
76.
关中地区水资源分布特点与合理开发利用模式   总被引:23,自引:1,他引:23  
该文在对关中地区水资源分布特点和水资源开发利用存在问题进行分析的基础上,从社会经济环境协调发展角度,根据区内水资源条件、开发利用潜力和环境状况,全面系统地提出了关中地区水资源合理开发利用的4种模式,在此基础上,根据地质、地貌、水文地质条件和水资源分布特征,进一步细分为8种亚模式,分析研究了各种亚模式水资源赋存规律、利用现状、开发潜力和合理利用方向,从而为水资源宏观开发利用指明了方向,也为关中地区水资源配置、规划与管理提供了科学依据。  相似文献   
77.
根据金川矿区充填管道系统的运行情况,结合充填实践经验,建立了充填管道系统的失效模式与影响分析法(FMEA)分析表,得出系统存在10种失效模式。针对FMEA分析表中失效影响存在较大模糊性而难以有效估计的特点,引入模糊评估方法来进行分析。通过该矿区充填管道系统各失效模式产生失效影响的模糊评估,得到不同失效模式对系统可靠性影响的排序结果。结果表明:该方法的评估结果与实际情况比较吻合;可以使分析定量化,有助于工程人员充分利用系统模糊信息;该方法也能用于其他系统失效模式影响的模糊评估。  相似文献   
78.
温泉生态旅游是未来温泉旅游的发展方向。温泉生态旅游非常适合在温泉资源丰富而生态环境较脆弱的喀斯特地区开展。基于对贵州省息烽温泉资源开发利用现状的调查,对息烽温泉生态旅游的发展思路、开发模式和运行机制进行了初步研究,希望能为该区域发展温泉生态旅游提供决策参考。  相似文献   
79.
Maritime transport has been playing a decisive role in global trade. Its contribution to the air pollution of the sea and coastal areas has been widely recognized. The air pollutant emission inventories of several harbors in China have already been established. However,the emission factors of local ships have not been addressed comprehensively, and thus are lacking from the emission inventories. In this study, on-board emission tests of eight diesel-powered offshore fishing ships were conducted near the coastal region of the northern Yellow Bo Sea fishing ground of Dalian, China. Results show that large amounts of fine particles( 0.5 μm, 90%) were found in maneuvering mode, which were about five times higher than those during cruise mode. Emission rates as well as emission factors based on both distance and fuel were determined during the cruise and maneuvering modes(including departure and arrival). Average emission rates and distance-based emission factors of CO, HC and PM were much higher during the maneuvering mode as compared with the cruise mode. However, the average emission rate of Nitrous Oxide(NOx) was higher during the cruise mode as compared with the maneuvering modes. On the contrary, the average distance-based emission factors of NOxwere lower during the cruise mode relative to the maneuvering mode due to the low sailing speed of the latter.  相似文献   
80.
本文分别以连续曝气和间歇曝气方式长期运行两套亚硝化移动床生物膜反应器,对比分析两种曝气方式下亚硝化生物膜特性差异和变化.研究表明,连续曝气和间歇曝气均可实现亚硝化生物膜生长(Kd> 0),但间歇曝气下生物膜连续脱落对生物总量基本无影响,生物膜生长过程更加稳定,且当亚硝化运行稳定后,间歇曝气可获得更高的生物总量(1.42g/m2).而连续曝气下生物膜可获得更高的蛋白质/多糖(PN/PS=1.8~2.0)和蛋白质/挥发性固体(PN/VS=0.145)以及更低的腐殖质/挥发性固体(HS/VS=0.05)和死细胞占比(13.66%).这说明连续曝气下生物膜中活性生物量占比更高,惰性生物量占比更低,活细胞占比更高,因而生物膜活性更高,微生物代谢更活跃.荧光实时定量PCR结果显示,以连续曝气运行的MBBR生物膜中亚硝化菌总量远高于间歇曝气,连续曝气更利于亚硝化菌的生长富集(2.36copies×108/g > 0.25copies×108/g).  相似文献   
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