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411.
锅炉烟尘排放浓度测量的不确定度评定   总被引:1,自引:0,他引:1  
如何对测量结果的不确定度进行合理评定,一直是困扰检测实验室的一个难题。根据环境监测的特点,通过实例,阐述了烟尘排放浓度测量不确定度评定的方法,对废气监测领域测量不确定度评定具有现实意义。  相似文献   
412.
Abstract

The accumulation of chlorophenols, including 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP), from river sediments from southern Taiwan were studied. Through simple or more exhaustive extractions, the results showed that 99% of the samples containing 2,4,6-TCP and PCP could be removed by simple extraction. the concentrations were found to range from non-detectable to 16.60 ngg1 for 2,4,6-TCP and to 25.02 ngg1 for PCP. Partition coefficients (Kp) were 0.71, 0.74 mlg1 for 2,4,6-TCP, 1.35 and 1.41 mlg1 for PCP. Biodegradation by DCP-adapted or unadapted anaerobes in sediment was carried out. During 21 days' incubation, the complete degradation time for 2,4,6-TCP in DCP-adapted anaerobic, unadapted anaerobic, and unadapted aerobic conditions were found to be 9, 10, 12 days for N3 sediment, and 8, 10, 11 days for N6 sediment, respectively; for PCP it was 19 days, without degradation, 14 days for N3 sediment, and 13, 17, 10 days for N6 sediment, respectively. the biodegradable products were identified as 2,3,4,5-tetrachlorophenol (2,3,4,5-TeCP), 3,4,5-TCP, 3,5-DCP, 3-MCP, phenol, methylphenol, and benzoate for PCP, and 2,4-DCP, 4-MCP, phenol, methylphenol, and benzoate for 2,4,6-TCP.  相似文献   
413.
近年来随着中国工农业生产和经济建设的快速发展,中国已经进入突发环境事件频发期。然而,中国的突发环境污染事件应急体系仍处于初级应用阶段,不能满足事故频发期事故应对的要求。因此,建立科学的应急决策支持系统具有重大的意义。在决策支持系统中,智能算法处于核心地位。文章对人工智能领域的仿生智能算法在环境应急领域的应用作简要介绍,并明确了多技术集成化应用的研究方向,以期对今后的研究有所启发。  相似文献   
414.
The task of mitigating climate change is usually allocated through administrative regions in China. In order to put pressure on regions that perform poorly in mitigating climate changes and highlight regions with best-practice climate policies, this study explored a method to assess regional efforts on climate change mitigation at the sub-national level. A climate change mitigation index (CCMI) was developed with 15 objective indicators, which were divided into four categories, namely, emissions, efficiency, non-fossil energy, and climate policy. The indicators’ current level and recent development were measured for the first three categories. The index was applied to assess China’s provincial performance in climate protection based on the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. Empirical results show that the middle Yangtze River area and southern coastal area perform better than other areas in mitigating climate change. The average performance of the northwest area in China is the worst. In addition, climate change mitigation performance has a negative linear correlation with energy self-sufficiency ratio but does not have a significant linear correlation with social development level. Therefore, regional resource endowments had better be paid much more attention in terms of mitigating climate change because regions with good resource endowments in China tend to perform poorly.  相似文献   
415.
聚合氯化铝与聚磷硫酸铁絮凝除藻比较研究   总被引:1,自引:0,他引:1  
针对武汉市莲花湖湖水,采用聚合氯化铝(PAC)和聚磷硫酸铁(PPFS)进行絮凝实验,比较了两种无机絮凝剂的絮凝效果及原水处理前后藻类群落变化。主要结论如下:①PPFS与PAC的最佳投加量分别为1.5mg/L、2.0mg/L;②PPFS在去除藻类细胞、浊度和色度方面均优于PAC,当PPFS投加过量时,因水体中Fe3+过量分布,使水样色度去除率下降;③PPFS絮凝处理微囊藻为主体的水华原水时,其效果比PAC更好。本文研究后表明:PPFS是一种新型高效絮凝剂,其絮凝性能明显优于PAC,当水体以微型藻类为主时,可使用PPFS以替代PAC,能提高絮凝效果。  相似文献   
416.
从污水处理厂的核心需求和TPM模式的内涵分析中,论述了TPM模式应用于污水处理厂的意义和切入点,阐明在污水厂中应用TPM模式,首先应优化的是生产组织结构。并在日处理量2万吨的污水处理项目中,实例应用了TPM模式改造生产组织结构,精简了班组与人员,取得了运营成本低减和设备运行稳定性上升的成效,验证了该模式对于污水处理厂生产管理的显著效益。  相似文献   
417.
418.
城市污水再生利用中的消毒问题研究   总被引:2,自引:0,他引:2  
从保障再生水微生物安全的角度,考察了北方某污水处理厂污水处理工艺、混凝沉淀过滤工艺以及臭氧消毒对大肠杆菌和总细菌的去除效果。结果表明,污水处理厂进水中大肠杆菌数和细菌总数分别为105~109个/L和109~1011个/L,经过厌氧-缺氧-好氧组合工艺处理后两者分别降为103~106个/L和106~109个/L,再经后续混凝沉淀过滤工艺(混凝剂PAC投加量:15 mg/L Al2O3)处理,再生水中大肠杆菌和细菌总数仍分别高达102~105个/L和105~108个/L。对上述再生水进行臭氧消毒批量实验,在臭氧反应量为12 mg/L的条件下实现了对大肠杆菌的完全灭活,此时臭氧消毒运行费用为0.13元/m3左右。  相似文献   
419.
针对传统的物理、化学和生物除藻技术的缺陷,提出了利用电液压脉冲技术控制水体中藻类的新方法.基于电液压脉冲技术的工作原理,利用水泵抽取湖泊中的水体,在电液压脉冲产生的高压和高温作用下,对控制水体藻类的工艺流程进行了详细分析.理论分析和实验研究表明:电液压脉冲的除藻效果与其作用次数呈指数关系,放电产生的电磁场、等离子体、空化流和在放电区域内所发生的复合作用对液体具有强大的综合作用,它们瞬间同时对水体发生作用,因此可以杀菌和控制湖泊水体中的藻类,以达到保护环境的目的.同时,利用电液压脉冲技术控制水体中的藻类,根据水的污染程度,能耗仅为0.1~0.5 kWh/m3.  相似文献   
420.
In this study, the characteristics of organic phosphorus (Po) fractions in sediments of six lakes from the middle and lower reaches of Yangtze River region and Southwestern China Plateau, China were investigated using a soil Po fractionation scheme, and the relationships between Po, inorganic phosphorus (Pi) and pollution status were also discussed. The results show that the rank order of Po fractions was: residual Po>HCl-Po>fulvic acid-P>humic acid-P>NaHCO3-Po, with their average relative proportion 8.7:4.6:3.2:2.1:1.0. Po fractions, especially nonlabile Po, were significantly correlated with organic matter, Po and NaOH-Pi. Different distribution patterns of P fractions were observed in those two different regions. Po fractions in the heavily polluted sediments were higher than those in moderately and no polluted sediments, it is suggested that Po should be paid more attention in the lake eutrophication investigation.  相似文献   
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