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81.
To establish a sustainable society, it is necessary to understand the flows and stocks of materials. However, traditional material flow analysis requires large quantities of data relating to the consumption and trade of materials in the past and the lifetime distributions of end use. To overcome the problem that such data may not be available, we have proposed using nighttime light images to estimate the in-use stocks of materials in countries for which the data are unavailable. In the previous study, in-use steel stock for civil engineering and building in 2006 was estimated using nighttime light images. However, several aspects of the methodology must be improved, and time-series analyses using nighttime light images have not yet been performed. Therefore, in this study, we improved the estimation of in-use steel stock by using new geological information (i.e., LandScan population distribution data) and correcting the pixel area. We prepared radiance-calibrated nighttime light data for 2006 and 2010 and conducted time-series analyses of the in-use steel stock using the nighttime light data. The in-use steel stock for civil engineering and building in 2010 was found to amount to approximately 11.3 Gt, which was approximately 21% higher than that in 2006.  相似文献   
82.
Blast damage to storage tanks and steel clad buildings   总被引:1,自引:0,他引:1  
The 2005 Buncefield vapour cloud explosion showed the huge cost associated with blast damage to commercial property surrounding a major explosion incident. In most cases there was serious disruption to business activity; in many cases the buildings had to be demolished or abandoned for long periods until extensive repairs were carried out.Another key feature of this and other recent vapour cloud explosions has been the damage done to storage tanks. The blasts almost invariably cause immediate top and bund fires in any tanks surrounded by the vapour – even if they contain relatively high flashpoint materials such as diesel.The first part of this paper describes the patterns of damage observed in buildings in the industrial estates around Buncefield. Methods for assessing the degree of external and internal damage are presented.The second part of the paper deals with failure modes and ignition of various types of liquid storage tank during vapour cloud explosions. Again, the Buncefield data provides excellent examples that illustrate the importance of tank design, fill level, location relative to the cloud, etc.  相似文献   
83.
Twelve sediment cores were collected in July 2007 in open waters of western Bohai Bay, the Port of Tianjin, and the adjacent estuaries of the Haihe and Yongding Rivers. While overall concentrations of trace metals at incremental depths in these cores met the Marine Sediment Quality (GB18668-2002) criteria of China, the magnitude of both metal enrichment factors (EF) and geoaccumulation indices (I(geo)) suggested that pollution with Ag, Cd, Cr, Cu and Zn was occurring in the estuaries and Port. Risk analysis also suggested that Ag and Ni concentrations were sufficiently elevated as to cause adverse biological effects in the study area. Although metal concentrations in western Bohai Bay were of less concern, a positive relationship between EF values and excess (210)Pb activity for several metals suggested that their concentrations were increasing over time.  相似文献   
84.
Within pinnipeds, phocids and otariids show differing maternal care strategies. Phocids rear young out of body stores in a yearly cycle with a single stay ashore when the mother fasts while lactating, whereas otariids provision their young by repeated foraging trips to sea alternating with brief stays ashore where they suckle their young. In a previous optimality model, these differences have been interpreted as adaptations based on differing energy requirements of large (phocid) and smaller (otariid) species, and the time budget of the large elephant and the much smaller Antarctic fur seal were correctly predicted. Our refined model—extended to pinniped species of all sizes—predicts lactation strategies to shift from attendance cycles to 1-year cycles with increasing body mass and provides an explanation for the finding that phocid pups are weaned at lower relative mass than otariid pups. However, other predictions do not correspond to empirical findings. In particular, the model does not explain the behavior of large otariids and small phocids. Thus, maternal metabolic requirements alone appear insufficient to explain observed lactation patterns. In the light of our results, we discuss more generally the scope and limitations of optimality models when applied in a comparative framework to a group of related species.  相似文献   
85.
A non-homogeneous variable-elasticity-of-substitution production function is estimated using data for the Welsh coal industry. From 1961 to 1976 output declined, returns to scale increased and the elasticity of substitution fell. At the end of the period, the elasticity of substitution between capital and labour in the coal industry is still large and there may be room for greater employment in the industry at a time of high and rising unemployment, subject to other overall considerations. While marginal productivity of labour in physical terms has been stagnant, price rises in the industry in recent years have been in excess of what was needed to finance wage settlements. Perhaps price rises granted to the coal industry by the UK government were justified, but they require closer scrutiny.  相似文献   
86.
基于上海市建设生态型城市的长期目标,将港口作为城市生态系统中重要的子系统,对如何建设生态型港口提出了综合评价指标体系.通过筛选得到45项单因素指标,针对不同类型的港区有所分异,整个评价体系分为5个准则层(生态环境、经济效率、污染控制、环境管理、社会评价)和10个因素层(大气/声环境、生物资源、基底质量、经济发展、生产效率、循环经济、污染排放、清洁生产、环保投入、社会参与),并采用AHP(层次分析)法确定了各层次的权重分配.进而根据2005年上海港年均生产状况和2006年上半年的港区环境-资源调查,尝试对上海港7种主要类型(集装箱、件杂货/成品、多用途、干散、粮食港区、液散、客运)的15个港区进行了现状评估.然而,生态港评价系统的指标选取、权重制定、评估级别等实践与完善仍需要多学科和政府职能部门的参与.最后,项目还提出了水生态健康、航道淤积、生态风险、水陆景观等非定量生态港评价因子.  相似文献   
87.
节能减排是我国经济发展中必须解决的问题,特别是高耗能产业更应首当其冲。我国钢铁行业节能减排任务很重,但依靠科学技术的进步,提高了企业发展的内力,取得了一定的成绩。但是,钢铁业总能耗依然占到全国总能耗的14%以上,今后面临的节能减排任务仍很艰巨。  相似文献   
88.
钢渣深处理技术   总被引:1,自引:0,他引:1  
瞿仁静 《云南环境科学》2010,29(5):63-65,81
以昆钢本部及红钢所产的转炉钢渣作为研究对象,研究热泼钢渣的矿物组成,分析钢渣中有价金属的组成,确定不同的粒级、不同的磁场强度,采用干式磁选与湿式磁选相结合的“一段闭路破碎,磁滑轮磁选;一段开路磨矿,一粗一精选别”深度处理流程,应用于红钢钢渣磁选车间及昆钢钢渣磁选厂,获得良好的磁选指标。分析了项目实施过程中渣浆输送断流的原因,找出解决办法。总结了项目产生的效益。  相似文献   
89.
通过现场测试对包钢中水水质类型及其用于高炉循环冷却系统的现状进行了调查研究。确定了在现有条件下4#高炉循环冷却水系统的水质类型为腐蚀为主,兼有结垢;包钢中水为微量结垢和腐蚀型水质,随着浓缩倍数的增加逐步转化为严重结垢型水质。  相似文献   
90.
This paper reviews databases on material recycling (primary as well as secondary production) used in life cycle assessments (LCA) of waste management systems. A total of 366 datasets, from 1980 to 2010 and covering 14 materials, were collected from databases and reports. Totals for CO2-equivalent emissions were compared to illustrate variations in the data. It was hypothesised that emissions from material production and the recycling industry had decreased over time due to increasing regulation, energy costs and process optimisation, but the reported datasets did not reveal such a general trend. Data representing the same processes varied considerably between databases, and proper background information was hard to obtain, which in turn made it difficult to explain the large differences observed. Those differences between the highest and lowest estimated CO2 emissions (equivalents) from the primary production of newsprint, HDPE and glass were 238%, 443% and 452%, respectively. For steel and aluminium the differences were 1761% and 235%, respectively. There is a severe lack of data for some recycled materials; for example, only one dataset existed for secondary cardboard. The study shows that the choice of dataset used to represent the environmental load of a material recycling process and credited emissions from the avoided production of virgin materials is crucial for the outcome of an LCA on waste management. Great care and a high degree of transparency are mandatory, but advice on which datasets to use could not be determined from the study. However, from the gathered data, recycling in general showed lower emission of CO2 per kg material than primary production, so the recycling of materials (considered in this study) is thus beneficial in most cases.  相似文献   
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