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961.
In the first, the paper gave a retrospective analysis on the comprehensive assessment of circular economic development. According to the requirement of improving resource & environment efficiency, the paper designed an analytical framework for a comprehensive assessment of regional circular economic growth, which consists of the goal, object and technical line of the comprehensive assessment of regional circular economic development. Given that, the paper discussed the criterion for choosing the assessment index, the approaches of index's weighing determination, the means of data standardization, and the reference system of assessment index value and so on. According to the framework of regional circular economic development evaluation, the paper made a comprehensive evaluation of Jiangsu Province's circular economic development. The result shows that from temporal change, Jiangsu Province's circular economic development had different stages; from the spatial comparison, there is variance among different regions, which could be divided into different types according to the spatial variance and the relation between the development of circular economy and the aggregative index number. There was a remarkable correlation between circular economic development level and GDP or the 2nd industry GDP. Finally, the ?aper gives some suggestions on how to promote the development of drcular economy in Jiangsu Province.  相似文献   
962.
川中丘陵区土地资源的可持续利用——以乐至县为例   总被引:1,自引:0,他引:1  
川中丘区是四川省粮食经济作物的主产区,土壤肥沃、耕地少、土地利用复杂。以乐至县为例,探讨了该县土地资源的可持续利用。  相似文献   
963.
964.
陈曦川  李琳 《灾害学》1998,13(2):33-36
为加强洪灾研究工作,做好灾前预评估、灾中跟踪评估、灾后详细评估工诈,应用地理信息系统(GIS)技术,建立起海河流域西三洼(东淀洼、文安茬、贾口控)洪灾遥感监测背景信息系统。  相似文献   
965.
Contrast with artificial environment, the multi-level self-organizational system of nature has great gain. Sustainable material environment should respect nature: non-rubbish and super-cycle quality of natural ecosystem offers the material source of human development, fractal structure of nature offers new field of space and information source to this high-density and information-based society, dissipative structure of nature links the new system of energy with whole ecosystem organically, and life-chain regulation is the base of sustainable life environment. Nature guarantees the physical healthy environ- ment by its all-dimension healthy factor, constructs the mental healthy environment by its quality of co-ordinate and chaos, so that guarantees the whole emergence of sustainable development on the 'super-science' level In the view of sustainable development, construction, green economy and human health are basic fields. With the concept of ecosystem regulation, we can relate these fields organically and fulfill the task of human health, welfare and sustainable development. Ecosystem regulation is the base of sustainable development's new paradigm.  相似文献   
966.
Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes(including emission, distribution,speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010–2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment.  相似文献   
967.
968.
This work analyzes a process known as flash pyrolysis, which produces bio fuels using biomass for power generation. A life-cycle assessment of flash pyrolysis of wood waste was conducted to study whether a flash pyrolysis plant set up locally would be environmentally friendly. The results obtained show that the process of flash pyrolysis of wood waste is in fact environmentally friendly, and the process has little contribution to the environment. However, efforts still have to be made to address the global warming potential issue. Continuous research and developments must be carried out to further reduce the global warming potential of the flash pyrolysis.  相似文献   
969.
CESSNA172R飞机飞行操纵钢索故障原因分析   总被引:1,自引:0,他引:1  
CESSNA172R飞机飞行操纵(副翼、升降舵、方向舵、襟翼)系统钢索多次发生磨损、断裂故障,严重威胁了飞行安全。根据该机型结构设计特点,通过相似机型系统类比、数据可靠性分析等方法分析了各飞行操纵系统钢索失效的主要原因,提出了预防飞行操纵钢索失效的措施。通过调整飞机的操纵钢索系统的维护周期,改进钢索的检查和维护技术,提高飞机在全寿命周期中的安全可靠性。  相似文献   
970.
黄锦林  杨光华  钟志辉 《灾害学》2013,(1):88-91,97
水库库岸滑坡是水库工程建设中普遍存在的问题,尤其是河道型水库,库区狭长,滑坡点多面广,库岸滑坡现象严重。阐述了库岸滑坡的防治原则、思路和方法,并针对鹅公带古滑坡体进行了防治方案的分析比选。  相似文献   
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