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31.
文章以昆明市为例,分析了昆明市地下水水质现状及变化趋势,总结了地下水污染防治工作成效和存在问题。分析表明,由于长期未受到充分重视,昆明市地下水已呈现出污染加重的趋势。近年来,昆明市地下水污染防治取得了一定的成绩,但仍然存在监管能力不足、监测网络覆盖不全的问题。在此基础上提出了开展地下水环境状况调查评估、磷石膏堆场地下水污染防控与修复试点和进一步完善地下水环境监测网络的对策建议,为昆明市和其他南方城市做好地下水污染防治工作提供借鉴。  相似文献   
32.
采用实地观察法、文献调查法对沈阳市农村生活污水处理设施基本状况进行研究分析。结果显示:沈阳市已建成农村生活污水处理设施297处,有机废弃物产生量(干重)约为:剩余污泥637 t/a、湿地植物废弃物169 t/a。  相似文献   
33.
为了解重庆市九龙坡区城区和城郊大气污染物浓度特征,分析了城区和城郊国控空气站点2014年3月~2015年2月典型污染物的浓度变化。结果表明,除O_3表现出夏高冬低的季节变化趋势外,其它污染物均表现出冬高夏低的季节变化趋势。PM_(2.5)污染最严重,城区和郊区日均值超标率分别为31.4%和33.4%。城区和城郊的PM_(2.5)浓度之间没有显著性差异(p0.05),城郊O_3浓度显著高于城区(p0.01),NO_2、SO_2、CO和PM_(10)则是城区显著高于城郊(p0.01)。  相似文献   
34.
为了提高落后地区旅游开发的质量,分别从低碳环保旅游以及生态旅游两方面,研究环保因素对落后地区旅游开发的促进作用。提出低碳环保旅游,并分析低碳环保对落后地区旅游业可持续发展的意义,在落后地区旅游开发中实施低碳饮食、低碳住宿、低碳交通以及低碳能源的旅游开发模式。对中国落后地区生态旅游现状和意义实施研究,分析生态旅游对落后地区旅游开发的促进作用。最终给出了落后地区实现生态旅游开发的建议,构建落后地区低碳环保的新型生态旅游模式,实现落后地区旅游的可持续发展。  相似文献   
35.
Recently, the New Morris Method has been presented as an effective sensitivity analysis tool for mathematical models. The New Morris Method estimates the sensitivity of an output parameter to a given set of input parameters (first-order effects) and the extent these parameters interact with each other (second-order effects). This method requires the specification of two parameters (runs and resolution) that control the sampling of the output parameter to determine its sensitivity to various inputs. The criteria for these parameters have been set on the analysis of a well-behaved analytical function (see Cropp and Braddock, Reliab. Eng. Syst. Saf. 78:77–83, 2002), which may not be applicable to other physical models that describe complex processes. This paper will investigate the appropriateness of the criteria from (Cropp and Braddock, 2002) and hence the effectiveness of the New Morris Method to determine the sensitivity behaviour of two hydrologic models: the Soil Erosion and Deposition System and Griffith University Representation of Urban Hydrology. In the first case, this paper will separately analyse the sensitivity of an output parameter on a set of input parameters (first- and second-order effects) for each model and discuss the physical meaning of these sensitivities. This will be followed by an investigation into the sampling criteria by exploring the convergence of the sensitivity behaviour for each model as the sampling of the parameter space is increased. By comparing these trends to the convergence behaviour from Cropp and Braddock (2002), we will determine how well the New Morris Method estimates the sensitivity for each model and whether the sampling criteria are appropriate for these models. It will be shown that the New Morris Method can provide additional insight into the functioning of these models, and that, under a different metric, the sensitivity behaviour of these models does converge confirming the sampling criteria set by Cropp and Braddock.  相似文献   
36.
This study was conducted to evaluate the usefulness of various biological parameters for monitoring of workers exposed to methyl ethyl ketone (MEK). Fifty male workers from a large magnetic videotape factory participated in this study. Personal air samples were collected using 3M organic vapor monitors and analysed for MEK by gas chromatography with flame ionisation detector (FID). 10 mL of urine; blood (1 mL) and exhaled air were also collected at the end of an 8-hour workshift. The headspace GC method was applied for measurement of urinary and blood MEK. MEK in expired air was analysed directly by using a GC/FID.The correlation coefficients (r) between environmental MEK and all other biological parameters measured show significant positive relationships. The r for environmental MEK and urine MEK was 0.84; for blood 0.73 and for breath 0.64. The correlation coefficients between blood and urine was 0.72; blood and breath was 0.88 and urine and breath 0.60. These findings suggest that measurements of unmetabolised MEK in blood, exhaled air and urine can be used for biological monitoring of MEK exposure. Nevertheless, laboratory methodological assessment is in favour of measuring urinary MEK as it is non-invasive and does not have to be analysed immediately after collection.  相似文献   
37.
COD快速分析高氯废水的实验研究   总被引:7,自引:0,他引:7  
韩英 《干旱环境监测》2003,17(2):127-128
对水中氯离子含量超过10000mg/L时进行除氯的预处理,保证了分析数据的真实、准确、可靠。  相似文献   
38.
采用火焰原子吸收分光光度法测定鱼内脏及河流底泥中的铜。鱼内脏经组织捣碎机捣成匀浆后,加硝酸消解;底泥则经氢氟酸和高氯酸消化。该方法具有灵敏度高,精密度和回收率较好等特点。  相似文献   
39.
Conclusion  In this paper we have considered a specific environmental game emphasizing both control-prevention efforts and the propensity to pollute by a firm which adopts a given pollution abatement technology. A random payoff game was constructed and solved under a risk neutral assumption and quadratic utilities for both the firm and the environmental controller. The game thus defined, provides a wide range of interpretations and potential approaches for selecting a control-inspection policies to prevent environmental risks. There are of course many facets to this problem, which could be considered and have not been considered in sufficient depth. For example, more complex control mechanisms and liabilities, the effects of insurance and risk sharing, the application of cooperative efforts and subvention of pollution abatement investments (through tax incentives and their like), etc. have not been considered [5,7]. These are topics for further research. The basic presumption of this paper is that it is very difficult to fully enforce pollution prevention by firms, as a result, some controls are needed to ensure that firms be controlled so that appropriate efforts are carried.  相似文献   
40.
The complexity of today’s research problems increasingly demands that scientists move beyond the confines of their own discipline. In this special issue, the basics of a transdisciplinary framework are established and problems analyzed in a specific discipline are successfully integrated in this transdisciplinary network. The intent has been to go beyond only statements about the importance of enabling early stage researchers to work across disciplinary boundaries, and to show that important discoveries are being made at the intersection of disciplines. Embedding various research projects in a more global framework can meet the demands of an interdisciplinary or transdisciplinary approach (especially for early stage researchers) and contribute significantly to sustainable research.  相似文献   
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