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981.
杨洁  王洪涛  周君 《环境科学研究》2013,26(9):1029-1034
基于生命周期评价方法,建立了我国铁路运输的生命周期模型,包含电力机车和内燃机车的运行、基础设施建设、上游能源和原料生产等主要过程;采用我国2010年铁路货运统计数据、中国生命周期核心数据库(CLCD)等数据源,通过eBalance软件对铁路运输生命周期的环境影响进行了计算和分析. 归一化分析表明,铁路运输生命周期的主要环境影响类型为富营养化、酸化和可吸入无机物,三者分别占全国相应环境影响类型总量的0.92%、0.70%和0.62%. 对大理—保山段铁路实际建设数据的研究表明,铁路基础设施建设及原材料生产的各项环境影响类型对铁路运输生命周期环境影响的贡献在9.45%(富营养化)~73.55%(非能源资源消耗)之间,影响十分显著. 生命周期节能减排综合评价表明,铁路运输节能减排综合指标的主要贡献来自于初级能耗、NOx和CO2,三者分别占ECER(节能减排综合指标值)的30.90%、27.50%和21.60%. 电力机车运输的节能减排效果优于内燃机车运输,其节能减排综合影响比内燃机车低41.91%.   相似文献   
982.
基于工作不安全感的视角,分析员工不安全行为的影响因素。围绕这一中心问题,设计了包含工作不安全感、工作生活质量和安全行为的调查问卷,并向大型施工企业(集团)发放。利用回收问卷的数据,采用中介效应法对工作不安全感、工作生活质量和不安全行为之间的相关关系进行了实证分析。问卷结果显示:员工的工作不安全感越高,对工作生活质量的感知越低,对个体安全行为的影响作用也就越大。该结论丰富了员工安全行为的研究视角,为施工企业安全生产管理实践提供了参考。  相似文献   
983.
避难硐室的构建研究对硐室安全避险功能的实现具有重要意义。根据旬东井下人员分布及巷道布置情况,确定利用4-2采煤区现有巷道构建100人规模永久避难硐室;根据巷道尺寸、人均面积及设备体积等,计算得硐室有效宽度为4.6m,高度为3.5m,总长度为63.4m,人均面积为1.2m2;通过气密试验,测定0.135MPa避险区内外压差可达1980Pa;通过分析人员避险需求,确定旬东永久避难硐室生命保障系统由防火防爆系统、密闭缓冲系统、气幕隔绝系统、供氧系统、制冷除湿系统及附属系统组成。  相似文献   
984.
为确保水冷器的服役周期,针对大检修开工后水冷器内漏的问题,从设计寿命、使用检修以及定期检验等方面进行了讨论,在设计者根据工况特点合理确定水冷器设计寿命的基础上,使用单位和检验机构还应根据水冷器潜在失效模式有针对性地加强日常管理。建议水冷器的停工检修与定期检验应关注管束的使用寿命,以保证检修后水冷器能运行到下一检修周期。  相似文献   
985.
The environmental burdens of Chinese copper production have been identified and quantified in the context of typical technologies, materials supplies and environmental emissions by a life cycle approach. Primary and secondary copper production using copper ores and scraps, respectively, were analyzed in detail. The flash and bath smelting approaches and the recycling of copper scraps were selected as representative copper production processes. A quantitative analysis was also conducted to assess the influence of material transport distance in copper production. Life cycle assessment (LCA) results showed that resources depletion and human health contribute significantly to environmental burdens in Chinese copper production. In addition, the secondary copper production has dramatically lower environmental burdens than the primary production. There is no obvious distinction in overall environmental burdens in primary copper production by flash or bath smelting approach. However, resources depletion is lower and the damage to human health is higher for flash smelting approach. Ecosystem quality damage is slight for both approaches. Environ- mental burdens from the mining stage contribute most in all life cycle stages in primary copper production. In secondary copper production, the electrolytic refining stage dominates. Based on the life cycle assessment results, some suggestions for improving environmental performance were proposed to meet the sustainable development of Chinese copper industry.  相似文献   
986.
The effect of resveratrol was studied on the life span and motor activity of Drosophila melanogaster treated with manganese (Mn). Two days after emerging from the pupa, male wild type D. melanogaster were fed for 13 days with corn media containing 15?mM Mn. Thereafter, Drosophila were divided into six groups of 300 flies each: (1) the flies remained treated with Mn; (2) began treatment with 0.43?mM resveratrol (Mn-resveratrol group); (3) received no additional treatment (Mn-no treatment group); (4) simultaneously fed with Mn and resveratrol (Mn?+?resveratrol group). In addition, a control (5) with no treatment and another group (6) fed only with resveratrol after emerging from the pupa were included. All Mn-treated flies (group 1) were dead on the 25th day. The life span in the resveratrol group was 91?±?0.33 days (mean?±?S.E.M.) and in Mn-resveratrol flies was 83?±?2 days. These two values were significantly higher than those detected in the control (5) and Mn-no treatment (group 3) flies whose life span were 68?±?0.33 and 67?±?2.31 days, respectively. The Mn?+?resveratrol-fed flies had a markedly higher life span (31?±?1.53 days) than Mn-fed flies (23?±?0.88 days). In the flies that received Mn (Mn and Mn?+?resveratrol groups), the motor activity decreased significantly with respect to control (groups 5) and the Mn–resveratrol and resveratrol groups. In conclusion, resveratrol increased significantly the life span of Mn-treated D. melanogaster.  相似文献   
987.
SUMMARY

Significant interest in the concept of sustainable development exists amongst scientists, planners, policy makers and the public, and considerable effort and expenditure is made or envisaged at local, national and international levels to promote a more sustainable society. Until ‘green accounting’ and similar systems are made available and are implemented, the sustainability indicator will be the most effective tool available for monitoring progress towards a more sustainable society. Sustainability indicators are already available but are characterized by a poor or absent theoretical underpinning. This paper addresses this problem by proposing a methodological framework that can be applied to the construction of indicators of sustainable development. In order to be consistent with widely accepted definitions of sustainable development, considerations relating to the measurement of quality of life and ecological integrity are central to the methodology. The methodological framework has relevance to a variety of spatial scales and to geographically diverse areas (urban or rural, developed or developing countries) so that a suite of sustainability indicators can be produced that is tailored to the needs and resources of the indicator user, but which remains rooted firmly in the fundamental principles of sustainable development.  相似文献   
988.
The accommodation sector is the most demanding energy consumer among all building stock categories. This study quantifies an international tourist hotel in Taiwan to holistically estimate the greenhouse gas emissions of hotel accommodation services through a complete life cycle inventory. The study also investigates the difference between the carbon emissions of the baseline and reduction years to understand the effects of carbon emission reduction on the hotel industry. Results show that energy consumption is the main source of carbon footprint. However, the carbon emissions of other activities, such as the production and transportation of hotel amenities and laundry services, are 15.90% for the baseline year and 16.03% for the reduction year. These values are larger than the 5% cutoff rule according to PAS 2050. Thus, these factors should also be considered in assessing the carbon emissions of accommodation services. Hotel occupancy rate significantly affects carbon emissions during a one-night stay in a standard room as the functional unit. The selection of the functional unit should be considered in the hotel strategy. Although this case study involves an international tourist hotel in Taiwan, the findings and recommendations for improvements can be applied elsewhere.  相似文献   
989.
基于工资风险法的生命价值评估   总被引:1,自引:0,他引:1  
为评估安全工作因挽救人的生命而产生的收益和制定工亡赔偿标准提供理论依据,在分析工资风险法评估生命价值经济学原理的基础上,构建生命价值评估模型。设计调查问卷对98家企业的795名员工进行调查,评估被调查员工的生命价值,并利用调查数据验证模型的有效性。评估结果表明:员工的生命价值评估值呈正态分布;在95%的置信水平下,生命价值评估值的置信区间为[3 424.62,4 284.33]万元,平均值为3 854.48万元。  相似文献   
990.
直立结构上冰力作用是国际海洋石油工程界研究的一个热点,尽管很多学者建立了各种冰力破碎模型,但是这些理论模型实现对冰与直立结构交互作用过程的量化模拟还存有较多困难.针对胜利油田大量海上平台超期服役现状,选择渤海现场实测的随机冰力时程曲线,考虑腐蚀减薄、桩基冲刷、海生物附着等服役损伤,建立海洋延寿平台结构有限元模型,研究随机冰力作用下海洋延寿平台构件的时程响应,采用疲劳等效应力幅来描述随机冰激疲劳应力过程产生的疲劳效应,最后基于Miner线性累积疲劳损伤模型采用S-N曲线法评估平台构件的疲劳损伤,该方法为进行可适合工程应用的渤海延寿平台疲劳评估提供了思路.  相似文献   
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