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131.
The aim of the research was to evaluate, at site scale, the influence of freezing and freeze/thaw cycles on the survival of faecal coliforms and faecal enterococci in soil, in a climate change perspective. Before the winter period and during grazing, viable cells of faecal coliforms and faecal enterococci were detected only in the first 10 cm below ground, while,after the winter period and before the new seasonal grazing, a lower number of viable cells of both faecal indicators was detected only in some of the investigated soil profiles, and within the first 5 cm. Taking into consideration the results of specific investigations, we hypothesise that the non-uniform spatial distribution of grass roots within the studied soil can play an important role in influencing this phenomenon, while several abiotic factors do not play any significant role. Taking into account the local trend in the increase of air temperature, a different distribution of microbial pollution over time is expected in spring waters, in future climate scenarios. The progressive increase in air temperature will cause a progressive decrease in freeze/thaw cycles at higher altitudes, minimising cold shocks on microbial cells, and causing spring water pollution also during winter.  相似文献   
132.
International cooperation to address climate change now stands at a crossroads.With a new international regime for emissions reduction established by the Durban Platform, "New Climate Economics(NCE)" has become a research hotspot.The need for urgent action to combat climate change has prompted discussion on reforms of economic growth patterns and the energy system.The industrial civilization,therefore,now faces a transition towards a new pathway for ecological sustainability.NCE explores new economic concepts,theories,and analytical methods to design a balanced pathway for sustainable growth and emission reduction.Instead of getting trapped in discussions on allocation of emission reduction responsibilities and obligations among countries,NCE pays more attention to developing win-win multilateral cooperation mechanisms that facilitate collaborative RD and knowledge sharing.In addition,NCE studies incentives for low-carbon transition,turning carbon emission reduction into a domestic need for countries to increase their international competitiveness.To achieve the 2°C target,most countries around the world face challenges of insufficient emission allowances to cover expected emissions associated with their projected economic growth.As carbon emissions rights becomes an increasingly scarce resource,increasing the carbon productivity of the economy turns to be the critical path to address the dilemma of green or growth.NCE studies the historical evolution of carbon productivity for countries at different development stages as well as ways to enhance such carbon productivity.This type of study provides invaluable lessons for emerging economies to reach their own emission peaks without losing the momentum of growth.Replacing fossil fuels with new and renewable energy has proven to be an inevitable choice for reshaping the energy system and addressing climate change- it has already become a global trend.NCE studies incentives for new energy technology innovation and deployment provided by carbon pricing,and sheds light on the co-benefits of climate change mitigation,such as resource conservation,environmental protection,and energy security.The role of carbon pricing in promoting intemational RD cooperation and technical transfer will also be studied.The shift in consumption patterns is another key factor enabling a low-carbon transformation.Therefore,NCE also explores the theoretical work on new values of wealth,welfare and consumption,new lifestyles in the context of ecological civilization,concepts and implementation of low-carbon urban planning in developing countries,and the impacts of consumption pattern changes on social development,material production,and urban infrastructure construction.  相似文献   
133.
黑龙江省西部泰来县在典型风沙干旱区,环境极其恶劣的沙带上,通过多年的探索和实践,已创建了庄园式生态经济型治沙的有效成功模式,明显地改善了当地生产、生存、生态环境,同时取得了显著的经济效益和社会效益.  相似文献   
134.
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   
135.
综述了国内外丁二烯过氧化物研究进展,主要包括丁二烯过氧化物的危害性、成因、危险评价和热稳定性,并对今后的研究方向进行了展望。  相似文献   
136.
圆锥形零件冲压成形过程分析   总被引:1,自引:0,他引:1  
通过分析圆锥形零件变形毛坯上不同部分在成形中的作用,揭示了该类零件的冲压成形特点,得出了悬空侧壁部分的变形状态是该类零件成形的关键,而径向拉应力是实现侧壁部分成形的必要条件,同时也是这部分冲压成形成败的关键。为此,经力学分析得出了侧壁部分径向拉应力的解析式和造成圆锥形零件破裂的最大径向拉应力的计算式,为进一步研究提供了理论基础。  相似文献   
137.
简要介绍了 F_(81)、F_(835)、F_(838)、F_(881)和F_(882)的定义及测试方法,并用具体数据加以说明。F 值是薄钢板的成形性优劣性指标,具有方向性。其中,F_(81)在评定不同板厚、不同冲压级别的薄钢板成形性能时,显得更为敏感;而F_(83)系列(包括 F_(881)、F_(882)),由于采用同一结构形式的公式,只是因 A 的测试方法不同,对 F 值有微小的影响。F_(88)测试方法简便、准确并易于实现自动化,具有在大生产中应用的前景。  相似文献   
138.
第一章 总则 第一条为加强安全生产行业标准(以下统称安全生产标准)的管理,规范安全生产标准的制定和修订程序,根据《标准化法》、《标准化法实施条例》等有关规定,制定本规定。  相似文献   
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