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631.
针对我国河流湖泊水环境状况不容乐观现状,以日本琵琶湖、欧洲莱茵河、英国泰晤士河流域综合整治为例进行了分析研究,提出我国治理河流湖泊水环境需要5个方面开展工作:建立强有力的流域管理机构;坚决控制污染源;加大对环保事业的资金投入;政府经济政策向环保倾斜;把市场经济引入流域治理等。  相似文献   
632.
在水质监测及诸多行业的工业废水监测中,COD是一个必测项目,微波密封消解测定COD是一种新方法,此方法与国标(GBll914—89)重铬酸钾法回流测定COD相比,具有成本低、操作安全、快速便捷等优点,其测定结果同标准重铬酸钾回流法相比对线性相关系数r大于0.999,是值得推广使用的一种方法。但为了得到准确可靠的分析结果,提高测定COD的工作效率,必须严格把握好一些关键性的技术问题。  相似文献   
633.
水质毒性快速检测可以及时提供水体的污染信息,为突发事件的紧急处理和水质毒性的预警提供依据。常见的水质毒性快速检测技术主要包括基于细菌的发光检测技术、化学发光检测技术、呼吸作用的检测技术、光合作用检测技术、电化学检测技术等。文章综述了主要水质毒性快速检测技术的原理和技术现状,并展望了相关发展趋势。  相似文献   
634.
以地表水环境质量准标为基础,设定水体污染物的基准值,构建用于水体的一种环境质量评价的模型,利用快速模拟退火组合优化法对相关参数进行优化,而得到一个对多种水污染物都适用的综合水体环境质量评价指数公式。该公式形式简单,计算容易,评价结果具有可比性。  相似文献   
635.
绍兴污水处理厂二期工程采用的是延时曝气工艺,生物氧化池是其核心工艺所在,在实际运行中,生物氧化池中溶解氧的数值波动大,较难实现稳定控制,通常采用滞后调整的控制方式,易造成能耗增加。为合理控制供气量,降低运行成本,利用欧洲的智能供氧技术,在经过小试的基础上,对二期其中一组生物氧化池进行中试,通过对几个月的试验数据进行对比分析,溶解氧控制较为平稳,供风量有所降低,从而实现了安全供氧和经济供氧,推动污水处理厂的精细化操作向纵深化发展。  相似文献   
636.
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   
637.
Sustainability demands that managers deliberate effects on stakeholders and the environment alongside traditional profitability measures. This paper presents a case study suggested by the managers of a distribution firm that seeks to balance environmental impact with cost in an industrial distribution network configuration decision incorporating product returns, which is currently taking place. While this can be modelled using mathematical programming, nonlinear terms in the objective functions as well as the likeliness that a large number of combinations of binary decision variables result suggest that this will not be able to be relied upon for a solution. For this reason, we propose a heuristic that aims at finding the Pareto-efficient frontier, which managers can use to deliberate the best solution balancing cost and environmental impact, according to the relative trade-offs of various possible configurations. We illustrate this heuristic on the Italian region of Liguria, and further explore trade-offs juxtaposing the regions of Lombardi and Sicily. Lastly, various extensions for enhanced product recovery opportunities for returns are suggested.  相似文献   
638.
This paper addresses the issue of the sustainability imperative and its influence on outsourcing practice. The research initially finds that there is currently little or no work that explores sustainable or green outsourcing, other than in an information technology context. This lack of research on sustainable outsourcing practice in the industrial organisation sector led to the development of this research study. This exploratory study used a qualitative survey tool to investigate current industrial practice. Manufacturing managers in 57 organisations formed the survey sample. The data were analysed by comparison and clustering of responses of survey participants. This study contributes five key findings that demonstrate current industrial practice which includes: 32% of respondents state that sustainability is not a factor in their outsourcing decision making and 65% of small- and medium-sized enterprises had never heard of the ‘triple bottom line’ concept. Future research needs are identified and proposed highlighting that urgent development of research is required in outsourcing performance measurement and also in considering sustainability as a new manufacturing competitive priority.  相似文献   
639.
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   
640.
The two competitive closed-loop supply chains under our study include three members: two manufacturers and one retailer. In this paper, we focus on the management of the wholesale prices, the retail prices and the collecting prices for the two competitive closed-loop supply chains. On the assumption that the return rate of the used-products is an increasing function of the collecting price, we obtain the optimal wholesale prices, the optimal retail prices and the optimal collecting prices based on the following models: Model MMC (two manufacturers for collecting), Model MRC (manufacturer one and retailer for collecting) and Model RRC (retailer for collecting). Furthermore, by comparing the optimal results, we find that the retailer for collecting is the best channel for the two competitive closed-loop supply chains if the two manufacturers would like to transfer all of their cost savings from remanufacturing to the retailer. At the end, we illustrate a numerical example to analyse the impacts of the market share ratio and the substitute ratio of the two products on the optimal results.  相似文献   
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