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黑碳气溶胶(BC)因其显著的气候效应和对人类健康的危害而成为研究的热点。研究背景点位BC的浓度水平和来源特征有助于掌握BC在区域尺度上的辐射强迫特性和环境影响。2009年秋季在华南沿海某区域大气背景点进行了为期约40 d的BC在线观测。观测期间BC的平均浓度为(2.34±1.33)μg/m3,与其它区域背景点相比处于较高水平。利用中尺度天气研究和预报系统WRF模拟的高分辨率三维气象场数据驱动HYSPLIT-4反向轨迹模式,模拟观测期间每小时的气团轨迹,将所有轨迹分为来源特征明显的东北沿海、北方内陆、香港方向和东南海面方向四类。当受到东北沿海来源气团影响时,BC的浓度为平均水平的1.4倍,BC和CO有较好的线性相关关系,而其它三类气团影响时的BC浓度都低于平均浓度,且BC和CO的相关关系很差,说明来自东北沿海地区的较近距离区域传输是影响该背景点大气BC的主要源区。 相似文献
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危险废物填埋场的安全选址是销毁日本遗弃在华化学武器工作中的一项重要的技术工作。本文依据我国环境保护的法律法规及标准,并采用科学的方法对危险废物填埋场址的选择进行了论述和评价,即:首先通过分析场址选择的影响因素,制定出科学、合理、可行的场址选择技术方案;然后再按优劣顺序对拟选的5个填埋场进行科学评价;最后选出最优的填埋场。 相似文献
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Josefina L. Murillo-Luna 《Journal of Cleaner Production》2011,19(13):1417-1425
This study contributes to the knowledge of the difficulties or barriers found by firms when adopting proactive environmental strategies, providing empirical evidence from 240 Spanish industrial firms. A set of 25 barriers are initially evaluated by the managers of the sample firms and are grouped into four types of difficulties facing firms: external barriers, endemic limitations of the firm, limited environmental motivation and limited preparation of employees and operational inertia. The estimation of a structural equation model leads us to conclude that only the barriers identified as endemic limitations of the firm can be characterized as “effective barriers”, defined as problems preventing firms from progressing toward proactive environmental behavior. 相似文献
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R. AndrewsAuthor VitaeJ.M. PearceAuthor Vitae 《Journal of Cleaner Production》2011,19(13):1446-1454
As the economic costs of energy and the negative externalities associated with the combustion of fossil fuels threaten the economic viability of greenhouses in northern climates there is a renewed interest in the use of waste heat. This paper presents a technical and economic methodology to determine the viability of establishing waste heat greenhouses using the waste heat from industrial processes in northern climates. A case study is presented of an exchange between a tomato greenhouse and a flat glass manufacturing plant, which found the waste heat system is significantly more economic to operate than a purely natural gas system. 相似文献
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As a remedial option, the natural attenuation capacity of a petroleum contaminated groundwater at a military facility was examined. Hydrogeological conditions, such as high water level, permeable uppermost layer and frequent heavy rainfall, were favorable to natural attenuation at this site. The changes in the concentrations of electron acceptors and donors, as well as the relevant hydrochemical conditions, indicated the occurrence of aerobic respiration, denitrification, iron reduction, manganese reduction and sulfate reduction. The calculated BTEX expressed biodegradation capacity ranged between 20.52 and 33.67 mg/L, which appeared effective for the reduction of the contaminants levels. The contribution of each electron accepting process to the total biodegradation was in the order: denitrification > iron reduction > sulfate reduction > aerobic respiration > manganese reduction. The BTEX and benzene point attenuation rates were 0.0058-0.0064 and 0.0005-0.0032 day-1, respectively, and the remediation time was 0.7-1.2 and 2.5-30 years, respectively. The BTEX and benzene bulk attenuation rates were 8.69 × 10-4 and 1.05 × 10-3 day-1, respectively, and the remediation times for BTEX and benzene were 7.2 and 17.5 years, respectively. However, most of the natural attenuation occurring in this site can be attributed to dilution and dispersion. Consequently, the biodegradation and natural attenuation capacities were good enough to lower the contaminants levels, but their rates appeared to be insufficient to reach the remediation goal within a reasonable time frame. Therefore, some active remedial measures would be required. 相似文献
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传统有机磷、有机氯农药具有高毒性、持久性和环境激素效应,处于痕量和超痕量浓度水平都可能给人类生命健康和生态环境带来严重威胁和风险。由于农药及其副产物的历史残留、累积及跨界迁移和分布,农药厂搬迁厂址用于房地产开发场地环评具有很大困难。结合南方某市一大型农药厂搬迁厂址用于房地产开发项目的案例,探讨了该类场地评价中基础资料的搜集方法和环评中应遵循的理念和原则。 相似文献
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根据环境影响评价监测的要求,提出了环评监测中方案的细化、点位布设方面存在的问题,阐述了如何合理设置监测点位、准确把握采样方法、科学选择分析方法等问题。 相似文献
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