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51.
Recent research has highlighted the positive role of green areas in urban environments, providing numerous social, environmental and economic services, such as mitigation of the urban heat island effect, storm attenuation, increased water infiltration into the soil, reduction of noise and air pollution, among others. However, the maintenance of green areas may result in high consumption of water, reaching 50% of the total consumption in some municipalities, and energy, becoming a reason of concern. The present study aimed to integrate techniques and technologies that promote the automatic and efficient irrigation of urban landscapes, using alternative sources of energy and water, toward its sustainability. The conceptual unit was able to reduce in 64% the water consumed in irrigation. Rainwater met 69% of the demand and the photovoltaic system supplied all the energy required. The economic feasibility analysis showed that the conceptual unit is financially unfeasible, under the conditions of this study. However, with some interventions for reusing the surplus energy and water, and considering the higher fees charged by other cities, the investment became attractive. In this new scenario, the internal rate of return (15 years) was 27.3% and the discounted payback period was 4.9 years.  相似文献   
52.
Based on the analysis on the global economic crisis,climate change crisis and their mutual underlying reasons,the authors believe that low-carbon economy has become an inevitable choice to break through the dual crises,coordinate the economic development,and protect the global climate.The global trend of low-carbon economy finds expression in Green Recovery currently,while,in a long run,it will give rise to a new pattern of world competition in politics,economy,technology,trade and finance.The impact of the...  相似文献   
53.
The potential of commonly available green alga Ulva lactuca was investigated as viable biomaterials for removal of synthetic azo dye (Direct Yellow 12, DY-12) from aqueous solution. The results obtained from the batch experiments revealed that the ability of the U. lactuca to remove DY-12 from its aqueous solution was dependent on the dye concentration, pH, and algal biomass but less dependent on the particle size of the U. lactuca. The equilibrium conditions and kinetics of adsorption were investigated, and the adsorption kinetic was consistent with the pseudo-second-order model (R2=1). The adsorption isotherm followed only the Freundlich model with a correlation coefficient R2=0.99. This study demonstrated that the U. lactuca could be used as an effective biosorbent for the removal of DY-12 from its aqueous solution.  相似文献   
54.
In the Lister region in the southern part of Norway, attempts are currently being made to facilitate for a green shift. The paper discusses two different approaches towards such a challenge. The first is procedural, where success or failure hinges on the methods applied in the effort to convince locals to incorporate climate considerations. The alternative is to reflect upon how a green ideology blends into pre-existing ideological elements in the region. It is claimed that an important reason for the failure so far to place the environment at the core of regional development, is that too much emphasis has been put on the first approach, on procedure and dialogue, whereas few efforts have been made to understand the structure of the discursive terrain in the region. What prevents a green shift has less to do with methods and is more connected to the dominance of a logic of economic growth and the fact that locals are confident that nature is already dealt with in a sensible manner. The conclusion is that we need to understand what people are concerned about and what prevents them to change, before we start telling them how to think and do development.  相似文献   
55.
As green infrastructure gets its attention in hazard mitigation, it is necessary to improve general understanding on what makes green infrastructure important for hazard and resiliency research. To better understand how green infrastructure fits with more traditional notions of structural and nonstructural mitigation, this study examines the relationship between green infrastructure and ‘structural and nonstructural’ mitigation approaches for hazard mitigation. Also, this study discusses a new measurement of locational aspects and spatial patterns of green infrastructure by utilizing high-resolution data in urban areas, and its potential implementation in hazard mitigation. Compared to previous research using land-use land-cover datasets, the normalized difference vegetation index (NDVI) utilizing National Agriculture Imagery Program dataset provides an ability to capture green infrastructure in greater detail. A visual comparison suggests that the NDVI data are able to capture and identify more types of ‘green’ land uses in Harris County. The total green infrastructure percentages for Harris County, Texas, based on 1-m high resolution were found to be 61.5% of the area, compared to the 51.5% based on the National Land Cover Database. This study provides support for utilizing high-resolution data to establish guidelines for green infrastructure’s spatial characteristics and sustainable hazard mitigation. The outcomes of this study will be helpful in the strategic planning and implementation of green infrastructure in urban areas with hazard issues.  相似文献   
56.
There are multiple lines of compelling evidence, mostly from population-based studies, supporting that green tea consumption is associated with reduced risk of several human malignancies. Epigallocatechin gallate (EGCG) is a major antioxidant present in green tea. Chemopreventive effects of EGCG have been extensively investigated and well documented. These include inhibition of metabolic activation of carcinogens and/or stimulation of their detoxification, scavenging of reactive oxygen species, induction of apoptosis or differentiation of malignant or transformed cells, suppression of tumor promotion, inhibition of angiogenesis or metastasis, etc. EGCG targets many intracellular signaling molecules and events responsible for malignant transformation or abnormal cell proliferation, and NF-κB and AP-1 appear to be two of most potential targets of EGCG in its exerting chemopreventive activities.  相似文献   
57.
碘酸钾氧化甲基绿褪色光度法测定痕量锡   总被引:3,自引:0,他引:3  
研究了稀磷酸介质中痕量锡催化碘酸钾氧气甲基绿的褪色反应及动力学条件,建立了高灵敏度测定痕量锡的新催化光度法.方法的灵敏度为2.4×10-12g/mL,线性范围为0~0.12μg/L.用于人发、水样及矿石中痕量锡的测定,结果满意.  相似文献   
58.
万群 《环境导报》2000,(5):19-20
“W型低NOx环保燃烧器”采用先进的复合多级混合式雾化技术,强化喷射、混合和扩散,燃烧充分从而控制NOx生成。  相似文献   
59.
赣闽浙三省接合区砂金资源分布广泛,尤以赣东北乐安江、昌江水系最富。本文是在对该区野外调查,取样分析和典型砂金矿床、矿点地质环境分析的基础上,认为冲积型砂金富集与矿源层分布,水系发育规模及地貌条件,含金物质搬运距离,水动力条件,沉积界面微地貌及合金物质沉积后埋藏状况有密切关系,掌握砂金沉积学特点有利于资源的勘探和开发。  相似文献   
60.
随着可持续发展战略在世界范围内的实施,铁路在实现交通运输系统可持续发展战略中的重要地位和作用,已成为许多国家的共识;通过对可持续发展在交通运输系统中的意义的讨论,具体阐述了可持续性发展的绿色铁路内涵;分析比较了铁路与其它各种运输方式在实现交通运输系统可持续性发展中的优势,并通过分析当前我国铁路网整体能力严重不足,运输紧张的状况,指出大力建设绿色铁路是我国可持续发展交通运输体系的优选方式.  相似文献   
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