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91.
钢铁企业含锌尘泥资源化利用途径分析评价   总被引:1,自引:1,他引:0  
通过分析锌元素进入钢铁制造流程的渠道,明确了钢铁企业含锌尘泥的来源与循环路径。根据含锌尘泥的循环途径,综合分析比较国内外含锌尘泥的不同利用方式和工艺——改变循环路径、物理选矿法、火法工艺以及湿法工艺。本着钢铁工业与锌冶炼之间形成工业化生态链的思路,提出了钢铁企业含锌尘泥的处理原则和资源化利用模式。  相似文献   
92.
全氟化合物的生物富集效应研究进展   总被引:5,自引:0,他引:5  
研究污染物的生物富集效应,对于预测污染物在生物体内的含量、建立环境标准以及评估污染物的生态风险具有重要的意义。结合近年来国内外报道的有关全氟化合物(PFCs)的生物浓缩因子(BCF)、生物富集因子(BAF)、生物放大因子(BMF)和营养级放大因子(TMF)等参数,对PFCs的生物富集效应及其影响因素进行了综述。研究结果表明,氟代碳原子数高于7的PFCs一般在生物体或食物链(网)上具有生物富集效应,而氟代碳原子数低于7的PFCs的生物富集效应较低。PFCs的理化性质(碳链长度、碳链末端基团类型和是否含有支链等)、生物的种类及其生理生化参数(体长、体重和性别等)和环境条件(生态系统的组成、水温和污染物含量等)等都影响PFCs在生物体内或食物链(网)上的富集。综观当前研究成果,PFCs在食物链(网)上生物放大效应研究主要集中于极地地区海洋食物网,应加强其他区域(特别是典型污染区域)、各种类型食物网(如淡水食物网和陆生食物网)上PFCs的生物富集效应及其影响因素研究,为全面评估PFCs的生态风险提供基础数据。  相似文献   
93.
为节省资源,留最窄护巷煤柱,在借用FLAC3D模拟软件掌握不同护巷煤柱宽度下巷道围岩应力应变后,结合模拟的结果和实验室试验新材料GRT-201加固后的煤岩体强度指标,最终确定煤柱留设宽度为2m,较正常煤柱宽度留设减小了20多米.现场操作后巷道的变形率控制在5%以内,大大降低留设煤柱宽度的同时保证了工作面的正常接替和安全回采.  相似文献   
94.
Green supply chain management (GSCM) integrates ecological concepts with those of supply chain management in order to minimize energy and material usage and to reduce adverse impacts of supply chain activities on the environment. GSCM implementation in mining industries depends largely upon certain factors which are influenced by human behaviours. Human behaviour is dynamic in nature and the relationships between them continuously evolve and change. In this ever-changing context, therefore, identifying and ranking the behavioural factors that affect GSCM implementation becomes essential. This can be taken as a reference by the decision makers while deciding the hierarchy of action necessary for effective implementation of green practices in mining supply chains. The present research attempts to explore various behavioural factors affecting GCSM practices and their interactions which help to attain green-enabled needs. Interpretive structural modelling (ISM) is employed in this research to extract the interrelationships among the identified behavioural factors.  相似文献   
95.
Corporate environmental responsibility in the supply chain   总被引:1,自引:0,他引:1  
A continuing trend in outsourcing increases the complexity of supply chains. Global supply chains extend over numerous echelons of countless companies. In parallel, the company-internal view on corporate environmental responsibility is being challenged as customers and legislation alike broaden a company's environmental responsibility to include organisations' upstream as well as downstream in the supply chain. Therefore, the aim of this study was to examine corporate environmental responsibility beyond corporate boundaries, i.e. in the supply chain. A cross-industrial study based on 16 case studies in Finnish trans-national corporations sheds light on various dimensions of corporate environmental responsibility upstream and downstream of product and process supply chains. Conclusions were drawn for corporate environmental responsibility as well as for the role of supply chain management in extending environmental demand over several echelons and diverse industries.  相似文献   
96.
Several global corporations have been severely criticized by different lobbying groups for the impact of their operations on the natural environment and on the local communities. Because corporate operations cannot be studied in isolation but rather as a part of a large network often referred to as a supply chain, this paper investigates the potential link between supply chain characteristics and sustainable development at the country level. In particular, the linkage between supply chain strength, generally defined as the number and quality of the suppliers and customers in a country, and the three dimensions of sustainable development namely environmental performance, corporate environmental practices, and social sustainability is assessed. Using archival data from The Global Competitiveness Report (2004–2005) and the 2005 Environmental Sustainability Index, a statistical assessment of the linkage was conducted. The results indicate that supply chain strength is positively linked to all three dimensions of sustainable development.  相似文献   
97.
Does copper reduce cadmium uptake by different rice genotypes?   总被引:4,自引:0,他引:4  
A hydroponics experiment was conducted to investigate the effect of copper (Cu) on cadmium (Cd), calcium (Ca), iron (Fe), and zinc (Zn) uptake by several rice genotypes. The experiment was carried out as a 2×2×4 factorial with four rice genotypes and two levels of Cu and Cd in nutrient solution. Plants were grown in a growth chamber with controlled environment. The results showed a significant difference between the biomass of different rice genotypes (P 〈 0.001). The Cd and Cu concentration in the solution had no significant effect on the biomass. The addition of Cu significantly decreased Cd uptake by shoots and roots of rice (P 〈 0.001). The Cd concentration did not significantly influence Ca uptake by plants, whereas the Cu concentration did (P = 0.034). There was a significant influence of Cd on Fe uptake by shoots and roots (P 〈 0.001, P = 0.003, respectively). Zn uptake decreased significantly as the addition of Cd and Cu increased in shoots. We concluded that Cu had significant influence on Cd uptake. The possible mechanisms were discussed.  相似文献   
98.
城市间空气污染控制的马氏链模型   总被引:1,自引:0,他引:1  
根据城市间空气污染物相互扩散和无后效性的特点,应用马尔可夫随机过程理论,先建立各城市污染物浓度状态转移方程,再由城市间污染物浓度状态形成一个吸收链。建立城市间污染物排放控制的马氏链模型。通过模型求解,得出了城市间空气污染物浓度达到国家排放标准的条件,最后应用数值计算软件MAT-LAB,编写了一个城市间空气污染控制的通用程序,它能在保证城市空气质量的前提下,快速准确地计算出控制区内各污染源污染物的最大允许排放量,这对环保部门进行城市空气污染物排放量控制工作具有实际意义。  相似文献   
99.
This research work focuses on the application of life-cycle assessment methodology to determine the carbon footprint of different players involved in a supply chain of the textile sector. A case study of a product by a textile leader company was carried out. This study demonstrates that, in the textile chain, the main contribution to the greenhouse effect is provided by the electrical and thermal energy used and by the transportation (since different production phases are delocalised in a wide range that goes from South Africa, Italy, Romania and all around the world, from the distribution centre to the stores). The Monte Carlo analysis has been used in order to obtain, for each calculated impact, not only the average value but also the distribution curve of the results characterised by uncertainty parameters. Moreover, a sensitivity analysis was carried out to evaluate the impact of management choices such as:

??a change in the transportation modality, from aeroplane to boat;

??a combination of road and rail transportation; and

??a selection among suppliers that allows the firm to cut environmental impacts.  相似文献   
100.
In this research a closed loop supply chain is designed which incorporates reverse logistics and forward logistic system simultaneously. In the design of reverse logistic system, recovery options are embedded in traditional supply chain for treating returned products. The recovery system includes collection centres, remanufacturing plants and disposal centres. Since the product return is supply driven, there is an uncertainty about it. In the proposed configuration for closed loop supply chain, the optimised configuration for supply chain in terms of locating recovery plants is developed. Accordingly, a fuzzy mixed integer linear programming model develops to deal with the uncertainty of returning products by customers. A general-purpose solver (LINGO 8.0) and a Meta heuristic approach (genetics algorithm) are implemented to solve the proposed model. The answers are compared by defining indexes and then the optimal answer, configuration and variables are identified. This solution will suggest a new design of supply chain network in which waste of materials is minimised and the new raw materials are necessary only when the used products may not be recovered by recovery options.  相似文献   
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