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401.
监测数据法在工业污染核算中的若干问题探讨   总被引:1,自引:0,他引:1       下载免费PDF全文
简述了监测数据法应用于污染核算的工作流程.指出了监测数据法使用中监测数据本身、环境统计中以及动态更新中监测数据使用存在的主要问题,提出了应加强监测管理、钻研监测技术,提升监测数据质量,为污染核算奠定基础;修订、完善监测数据法的相关技术规定并督促严格执行;正确处理监测数据,从技术层面改进污染核算质量;加强监测数据法核算的...  相似文献   
402.
Aluminosilicate clay mineral (ACM) is a kind of typical raw materials that used widely in manufacturing industry owing to the abundant reserve and low-cost exploring. In past two decades, in-depth understanding on unique layered structure and abundant surface properties endows ACM in the emerging research and application fields. In field of solar-chemical energy conversion, ACM has been widely used to support various semiconductor photocatalysts, forming the composites and achieving efficient conversion of reactants under sunlight irradiation. To date, classic ACM such as kaolinite and montmorillonite, loaded with semiconductor photocatalysts has been widely applied in photocatalysis. This review summaries the recent works on ACM-based composites in photocatalysis. Focusing on the properties of surface and layered structure, we elucidate the different features in the composition with various functional photocatalysts on two typical kinds of ACM, i.e., type 1:1 and type 2:1. Not only large surface area and active surface hydroxyl group assist the substrate adsorption, but also the layered structure provides more space to enlarge the application of ACM-based photocatalysts. Besides, we overview the modifications on ACM from both external surface and the inter-layer space that make the formation of composites more efficiently and boost the photo-chemical process. This review could inspire more upcoming design and synthesis for ACM-based photocatalysts, leading this kind of economic and eco-friendly materials for more practical application in the future.  相似文献   
403.
通过对上海市水环境主要污染物总量的分析,从政府管理角度,探讨“十一五”上海市水环境主要污染物总量控制核查方法。主要从污水收集管网建设和污水处理厂建设及运行、重点污染源监管、水环境质量改善三方面入手,通过计划申报、日常监控、实时预警来保证总量控制目标完成,并探讨了核查职责体系和信息发布程序及内容。  相似文献   
404.
王光焱 《环境科技》2008,21(3):61-64
重点从我国环境标准的环境质量标准与环境质量基准、环境质量标准和污染物排放标准的关系两个方面进行初步探讨,对当前我国缺少环境质量基准标准,不能满足环境管理要求的状况进行了分析。同时,对环境标准自身建设及其实施应用提出相应的建议和对策。  相似文献   
405.
• Quantification of efficiency and fairness of abatement allocation are optimized. • Allocation results are refined to the different abatement measures of enterprises. • Optimized allocation results reduce abatement costs and tap the abatement space. • Abatement suggestions are given to enterprises with different abatement quotas. For achieving air pollutant emission reduction targets, total pollutant amount control is being continuously promoted in China. However, the traditional pattern of pollutant emission reduction allocation regardless of economic cost often results in unreasonable emission reduction pathways, and industrial enterprises as the main implementers have to pay excessively high costs. Therefore, this study adopted economic efficiency as its main consideration, used specific emission reduction measures (ERMs) of industrial enterprises as minimum allocation units, and constructed an enterprise-level pollutant emission reduction allocation (EPERA) model with minimization of the total abatement cost (TAC) as the objective function, and fairness and feasibility as constraints for emission reduction allocation. Taking City M in China as an example, the EPERA model was used to construct a Pareto optimal frontier and obtain the optimal trade-off result. Results showed that under basic and strict emission reduction regulations, the TAC of the optimal trade-off point was reduced by 46.40% and 45.77%, respectively, in comparison with that achieved when only considering fairness, and the Gini coefficient was 0.26 and 0.31, respectively. The abatement target was attained with controllable cost and relatively fair and reasonable allocation. In addition, enterprises allocated different emission reduction quotas under different ERMs had specific characteristics that required targeted optimization of technology and equipment to enable them to achieve optimal emission reduction effects for the same abatement cost.  相似文献   
406.
Goal, Scope and Background Atmospheric sampling (gas and particles) of 5 phenols (phenol, m-cresol, p-cresol, o-cresol, pentachlorophenol) and 15 nitrophenols (3-methyl-2-nitrophenol, 3-nitrophenol, 4-methyl-2-nitrophenol, 5-methyl-2-nitrophenol, 2-methyl-3nitrophenol, 3-methyl-4-nitrophenol, 2,6-dinitrophenol, bromoxynil, 2,5-dinitrophenol, 2,6-dinitro-p-cresol, 2,4-dinitrophenol, ioxynil, DNOC, 3,4-dinitrophenol, dinoseb) on XAD-2 resin (20 gr) and glass fibre filters, respectively, were performed in 2002 by using 'Digitel DA80' high volume samplers. These measurements were undertaken in order to show spatial and geographical variations of concentrations and the role of traffic in the emissions of these compounds to the atmosphere. Methods Sampling were performed in Strasbourg (eastern France), in its vicinity (Schiltigheim) and in Erstein. Sites were chosen to be representative of urban (Strasbourg), suburban (Schiltigheim) and rural (Erstein) conditions. Field campaigns were undertaken simultaneously in urban and suburban sites during all the seasons during 4 hours at a flow rate of 60 m3.h-1, which gives a total of 240 m3 of air per sample. Period of sampling varied between 06h00 to 10h00, 11h00 to 15h00 and 18h00 to 22h00 in order to evaluate a variation of concentration during automobile traffic between urban, suburban and rural areas. Gas and particle samples were separately Soxhlet extracted for 12 h with a mixture of CH2Cl2 / n-hexane (50:50 v/v), concentrated to about 1 mL with a rotary evaporated and finally dried under nitrogen. Dry extracts were dissolved in 1 mL of CH3CN. Before analysis, extracts were sylilated by using MTBSTFA. Analysis was performed by GC/MSD in the SIM mode. Results and Discussion Partitioning of phenolic compounds between gas and particle phases seems to be mainly correlated with vapour pressure. Among phenolic compounds analysed, phenol, p-cresol, pentachlorophenol and 2.4-dinitrophenol were detected in all samples and emissions from traffic seems to be the major source for the presence of these compounds to the atmosphere. No increase of concentrations in autumn tend to confirm this hypothesis since, with the use of domestic heating in colder months, increases of PAHs concentrations were observed and these compounds are known to be emitted by all combustion processes. Pentachlorophenol is a special case since this molecule is only used as wood preservative. Its presence in all atmospheric samples, whatever the locations and the period of time is the consequence of its persistence. Conclusions and Perspectives These measurements demonstrate that phenols and nitrophenols are emitted to the atmosphere and further measurements, in order to confirm their sources, their behaviour and their potential impact to the air quality and to human health should be undertaken especially since the literature collected is relatively old. Concentrations of pentachlorophenol measured are very low and, due to its toxicity, further investigations should be undertaken. - * The basis of this peer-reviewed paper is a presentation at the 9th FECS Conference on 'Chemistry and Environment', 29 August to 1 September 2004, Bordeaux, France.  相似文献   
407.
城市降雨屋面、路面径流水文水质特征研究   总被引:24,自引:6,他引:18  
为研究城市硬质下垫面径流的水文过程与污染物浓度变化特征,对北京市2006年6-8月的4场降雨进行路面和屋面水文、水质过程同步分析.结果表明,径流曲线与降雨过程线形状类似,波动幅度相对较小,滞后于降雨过程线5~20 min,屋面径流系数在0.80~0.98之间;路面径流系数在0.87~0.97之间.径流污染物的浓度是由累积排放规律决定的,路面径流的污染物浓度高于屋面径流,径流中COD、TN、TP的浓度均超过地表水环境质量标准V类水要求.各类污染物之间的相关性均处于显著性水平R=0.1以上,屋面径流颗粒物与有机物和阴离子之间的相关关系较大(>0.5),而与氮磷等营养物质的相关系数较小(<0.5);路面径流中,TN、1P与颗粒物的相关性有所增加.径流中各类物质大多存在初期冲刷现象,并受到污染物种类、下垫面特征、降雨强度和雨型等因素的影响.SS初期冲刷现象较其它几类污染物更为明显,路面较屋面更容易形成初期冲刷,低强度降雨不容易形成有机物和营养物质的初期冲刷现象.控制初期径流污染是北京市径流管理的有效措施.  相似文献   
408.
面对排污许可证“一证式”监管的高标准、严要求,通过创新信息化管理手段,设计排污许可管理辅助系统,一是能够为企业提供服务,提升企业按证守法管理的规范性;二是能够为监管部门审计式核查提供技术支持,通过对数据的全面性、规范性、逻辑性进行分析,为现场执法提供支持,提升管理部门的行政监管效率,提升排污许可证管理的专业化水平,真正落实事中事后监管要求,提高监管执法效能。同时,也能为政策制定提供辅助决策支持。  相似文献   
409.
为了解氮磷浓度对生物操纵效果及同时恢复水生植被的影响,以小球藻、大型溞和金鱼藻分别作为浮游植物、浮游动物和大型沉水植物的代表,模拟自然条件研究了不同氮磷浓度对三者生长和相互作用的影响.结果表明:金鱼藻和小球藻共培养时,在氮浓度介于2.92~12.60mg·L-1、磷浓度介于0.06 ~0.85 mg·L-1,金鱼藻增长不明显,甚至出现负增长;而小球藻的增长率则远高于金鱼藻.小球藻和大型溞共培养时,氮、磷浓度分别为1.26~ 10.53 mg·L-1和0.04~1.16 mg·L-1时均占据优势,对小球藻的抑制效果显著,抑藻及氮磷去除效果明显好于金鱼藻和小球藻共培养,而且磷的去除效果优于氮.三者共培养时,在氮浓度介于3.15 ~23.92 mg·L-1、磷浓度介于0.07 ~0.64 mg·L-1时,大型溞与金鱼藻的增长率都较高,而小球藻则维持在较低的增长水平,水质改善效果较好;当氮、磷浓度分别升至25.95 mg·L-1和1.18 mg·L-1时,大型潘和金鱼藻的增长率均下降,水质变差.大型溞和金鱼藻的联合控藻效果好于其单一的控制效果,该效果明显受到氮磷浓度的影响.  相似文献   
410.
推动大气污染物排放总量控制 深化大气环境管理   总被引:1,自引:0,他引:1       下载免费PDF全文
本文分析了大气环境管理从“浓度控制”逐步过渡到“总量控制”与“浓度控制”相结合所必需的思想观念、技术方法、政策和制度上的相应转变,以及如何在现行管理体制的基础上分步实施大气污染物排放总量控制。   相似文献   
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