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851.
我国环境监测技术存在的问题及对策   总被引:7,自引:0,他引:7  
从监测结果的科学性、监测方法的系统性及应急技术的实用性角度,提出了目前我国环境监测技术存在的问题,指出应通过科学监测,反映真实的环境质量,研究有毒有害污染物的监测方法并使其标准化,加强突发污染事故的快速监测技术研究.  相似文献   
852.
阐述了加强环境空气监测点位管理的重要性,指出了目前环境空气监测点位管理中存在的问题,提出设置监测点位时,既要考虑监测点的位置和数量,又要考虑监测点周围的人为活动、流动污染源、固定污染源和面源的影响。  相似文献   
853.
介绍了固定污染源中挥发性有机物(VOCs)的主要采样方法,并重点介绍了动态稀释法在固定污染源中采样的应用。采用动态稀释法取样,对某汽车企业涂装车间的排放废气进行了定性分析,并对其中主要的10种VOCs进行了定量分析。研究了方法测定的稳定性,10种化合物相对标准偏差为9%~32%,符合工况变动范围。将不同采样时间及不同吸附材料的测定结果与在线监控数据进行比较,结果显示动态稀释法的测定结果均在实际工况波动范围内,说明该方法能够较好地满足汽车涂装行业VOCs的采样要求。  相似文献   
854.
以生态文明全面取代工业文明,是实现人类生存进步及经济可持续发展的唯一途径。以我国为例,在经历40年社会改革开放、经济高速增长之后,工业化、城市化、现代化所取得巨大成就的背后,是生态环境的严重破坏,尤其近年来"雾霾"成为生态环境治理中最为顽固的诟病。锅炉烟尘是造成雾霾现象的"主要元凶",从环境监测角度出发,加强锅炉烟尘监测过程及现场采样质量控制,精准地获取相关数据,能够为环境治理方案提供科学依据。但同时,锅炉烟尘监测及采样是十分复杂且具有系统性的工作,在整个过程中需要加强质量控制。本文列举相关注意问题,以供技术人员在操作中参考借鉴。  相似文献   
855.
Microbiologically influenced corrosion (MIC) is a microbial community assisted degradation of materials affecting chemical processing and oil and gas industries. MIC has been implicated in incidents involving loss of containment of hazardous hydrocarbons which have led to fires and explosions, economic and environmental impact. The interplay between abiotic environmental factors and dynamic biotic factors in MIC are poorly understood. There is a lack of mechanistic understanding of MIC and very few models are available to predict or assess MIC threat. Here we report on the development of a model to assess the susceptibility to MIC. The high-resolution model utilizes 60 independent nodes, including operational and historical failure analysis data, and is built by combining empirical relationships between the abiotic and biotic variables impacting MIC. Both static and dynamic Bayesian-network (BN) approaches were used to combine heuristic and quantitative states of variables to ultimately yield a susceptibility measure for MIC. A confidence-in-information metric was generated to reflect the amount of data used in the estimation. A susceptibility to MIC of 45%–60% was estimated by the model for ten different scenarios simulated using case-studies from literature. The susceptibility to MIC estimated by these scenarios was further interpreted in the context of these cases. This systems-based MIC model can be utilized as an independent estimator of susceptibility or can be incorporated as a sub-model within comprehensive safety threat assessment models currently utilized in industry.  相似文献   
856.
Three flare systems are modeled and total plant depressurization is investigated using dynamic simulations in order to access the debottlenecking potential. Usually, steady-state simulation of the flare network is used for sizing and rating of the flare system. By using dynamic simulations, effects from line packing in the flare system can be studied. The results show that peak flow during a dynamic simulations is significantly lower than the peak flow used in a steady-state case. The three systems investigated span a wide range in flare system size, both in terms of number of process segments disposing into the flare network, in terms of peak design rate, the flare network pipe dimensions and total hold-up volume. Generally, it is observed that the larger the flare system, the larger debottlenecking potential.  相似文献   
857.
高增润 《环境与发展》2020,(2):23-23,25
环境监测技术是通过分析环境中各种相关因素的变化情况来确定环境污染的源头,目前,随着我国工业化的发展,水体污染成了环境治理的头等难题,我们要加强对水污染的环境监测,改善水体质量,为人类提供优质的水资源。  相似文献   
858.
牛军 《环境与发展》2020,(2):115-116
本文主要针对雾霾天气背景下大气环境监测质量的提升路径展开深入研究,先阐述了大气环境监测质量的提升重要性,比如有利于提高环境污染的防治水平、有利于不断提高城市环境规划水平等,然后重点提出了几点可行的提升路径,主要包括制定大气环境监测质量保障体系、加强环境质量监测网络建设、加强大气环境监测采样管理、加强3S技术的应用、加强监测监察联动协调机制、扩大大气环境质量评价范围等,确保监测数据与完整性和准确性相符,确保大气环境监测质量的稳步提升,以创建节能减排、生态环保的节约型社会。  相似文献   
859.
薛璐 《环境与发展》2020,(1):153-153,155
随着新时代的全面到来,我国对于生态环境的重视程度也在不断提高,社会民众的环保意识也变得越来越高。在这种大背景下,环境监测科技得到了全面的发展,同时在我国各个地区也开始广泛的应用。本文先阐述了新形势下环境监测科技的发展现状,从信息化技术的深层次应用、形成多元化与多层次的监测技术格局、构成创新化的环境监测技术体系、逐步实现监测人员专业素质水平的提升四个方面,综合全面探讨了新形势下环境监测科技的发展与展望。  相似文献   
860.
Abstract: China has experienced a rapid land‐use/cover change (LUCC) during the 20th Century, and this process is expected to continue in the future. How LUCC has affected water resources across China, however, remains uncertain due to the complexity of LUCC‐water interactions. In this study, we used an integrated Dynamic Land Ecosystem Model (DLEM) in conjunction with spatial data of LUCC to estimate the LUCC effects on the magnitude, spatial and temporal variations of evapotranspiration (ET), runoff, and water yield across China. Through comparisons of DLEM results with other model simulations, field observations, and river discharge data, we found that DLEM model can adequately catch the spatial and seasonal patterns of hydrological processes. Our simulation results demonstrate that LUCC led to substantial changes in ET, runoff, and water yield in most of the China’s river basins during the 20th Century. The temporal and spatial patterns varied significantly across China. The largest change occurred during the second half century when almost all of the river basins had a decreasing trend in ET and an increasing trend in water yield and runoff, in contrast to the inclinations of ET and declinations of water yield in major river basins, such as Pearl river basin, Yangtze river basin, and Yellow river basin during the first half century. The increased water yield and runoff indicated alleviated water deficiency in China in the late 20th Century, but the increased peak flow might make the runoff difficult to be held by reservoirs. The continuously increasing ET and decreasing water yield in Continental river basin, Southwest river basin, and Songhua and Liaohe river basin implied regional water deficiency. Our study in China indicates that deforestation averagely increased ET by 138 mm/year but decreased water yield by the same amount and that reforestation averagely decreased ET by 422 mm/year since most of deforested land was converted to paddy land or irrigated cropland. In China, cropland‐related land transformation is the dominant anthropogenic force affecting water resources during the 20th Century. On national average, cropland expansion was estimated to increase ET by 182 mm/year while cropland abandonment decreased ET by 379 mm/year. Our simulation results indicate that urban sprawl generally decreased ET and increased water yield. Cropland managements (fertilization and irrigation) significantly increased ET by 98 mm/year. To better understand LUCC effects on China’s water resources, it is needed to take into account the interactions of LUCC with other environmental changes such as climate and atmospheric composition.  相似文献   
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