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801.
采用单一指标评价海水入侵程度存在片面性和不确定性,模糊综合评判法在一定程度上可解决单一指标评价带来的问题,但精准的评价结果需要采集大量的调查数据,其调查与检测成本较高。提出一种单因子界定联合模糊综合评判的海水入侵评价方法。该方法首先通过水文地质调查查明研究区地下水动力场,并以250mg/L氯离子浓度为界初步界定出海水入侵峰值线的位置;然后根据初步界定的海水入侵峰值界线,结合地下水流网及地形地貌分区设计数条地下水详查断面;最后建立模糊综合评价模型,对详查断面上的采样点进行综合评价,可得出海水入侵程度的综合评价结果。该方法在日照市山海天旅游度假区两城河地下水海水入侵现状评价中得到了有效应用,为经济、高效地实施海水入侵防治工作奠定了技术基础。  相似文献   
802.
Bacterial populations coexisting in the phyllosphere niche have important effects on plant health. Quorum sensing (QS) allows bacteria to communicate via diffusible signal molecules, but QS-dependent behaviors in phyllosphere bacterial populations are poorly understood. We investigate the dense and diverse N-acyl-homoserine lactone (AHL)-producing phyllosphere bacteria living on tobacco leaf surfaces via a culture-dependent method and 16S rRNA gene sequencing. Our results indicated that approximately 7.9%-11.7% of the culturable leaf-associated bacteria have the ability to produce AHL based on the assays using whole-cell biosensors. Sequencing of the 16S rRNA gene assigned the AHL-producing strains to two phylogenetic groups, with Gammaproteobacteria (93%) as the predominant group, followed by Alphaproteobacteria. All of the AHL-producing Alphaproteobacteria were affiliated with the genus Rhizobium, whereas the AHL-producing bacteria belonging to the Gammaproteobacteria mainly fell within the genera Pseudomonas, Acinetobacter, Citrobacter, Enterobacter, Pantoea and Serratia. The bioassays of supernatant extracts revealed that a portion of the strains have a remarkable AHL profile for AHL induction activity using the two different biosensors, and one compound in the active extract of a representative isolate, NTL223, corresponded to 3-oxo-hexanoyl-homoserine lactone. A large population size and diversity of bacteria capable of AHL-driven QS were found to cohabit on leaves, implying that cross-communication based AHL-type QS may be common in the phyllosphere. Furthermore, this study provides a general snapshot of a potential valuable application of AHL-producing bacteria inhabiting leaves for their presumable ecological roles in the phyllosphere.  相似文献   
803.
The stamp-charging coke making process has some advantages of improving the operation environment, decreasing fugitive emission, higher gas collection efficiency as well as less environmental pollution. This article describes the different structure strength and high temperature thermal properties of 4 different types of coke manufactured using a conventional coking process and the stamp-charging coke making process. The 4 kinds of cokes were prepared from the mixture of five feed coals blended by the petrography blending method. The results showed that the structure strength indices of coke prepared using the stamp-charging coke method increase sharply. In contrast with conventional coking process, the stamp-charging process improved the coke strength after reaction but had little impact on the coke reactivity index.  相似文献   
804.
The evolvement of morphology and structure of the coal with different metamorphic degrees during coking process in the vertical furnace was investigated by infrared Image detector. Moreover, the temperature distribution in the radial direction and the crack formation were also studied in heating process. The results show that the amount of crack and the shrinkage level of char decrease with the coal rank rising. In addition, the initial temperature of crack formation for char increases with the coal rank rising.  相似文献   
805.
Long flame coal are abundant and widely distributed in China, but the resource utilization is quite low, the production efficiency is not high. Stamp-charging coke making technology can bend some long flame coal, which can reduce production cost and expand the coking coal resources. The long flame coal of different mass fraction is added into prime coking coal including fat coal from Longhu, 1/3 coking coal from Xinjian and coking coal from Didao in experiment. The swelling pressure is tested on-line detection using pressure sensor in coke making process, and the pores are observed by scanning electron microscopy. The results show that, the swelling pressure first increase and then decrease with the temperature increased and the maximum swelling pressure reduces gradually with mass fraction of the Long flame coal from Shenmu increased in coke making process. The SEM images of resultant coke display that the coke get more and more loose and the amount of pores is increased with mass fraction of the long flame coal from Shenmu increased. The amount pores and the pore diameter both is minimum for coking coal from Didao as prime coking coal under the same fraction of long flame coal.  相似文献   
806.
工业园区大气环境影响预测的难点主要在于进入园区项目的不确定性使得预测工作没有较为精准的基础数据。因此,要在充分分析园区定位、产业特征和入园行业的基础上,以宏观与微观相结合的方式进行预测,设立多种情景分析;同时充分分析园区的所在地区的环境承载力,才能对园区建设对大气环境的影响有较为准确的把握。以内蒙古蒙大新能源化工基地为例,简要说明。  相似文献   
807.
本文通过多年来的工作实践和管理经验,针对新时期环境监测及污染源监测工作的特殊要求,围绕环境监测站的定位,软、硬件建设及监测数据管理的重要性,从多方面、多角度进行了详尽的阐述,提出了有针对性的对策与建议.  相似文献   
808.
当前,我国正处于经济建设的高速发展时期,环境保护工作的发展面临着前所未有的机遇和挑战。环境监测作为环境保护管理中的最重要手段,贯穿于环境影响评价的全过程,其监测数据反映了环境质量状况和污染物排放情况,是环境污染预测的基础,是实施总量控制必不可少的手段,在环境影响评价体系中有着重要的作用。  相似文献   
809.
战略环境影响评价是指对法律、政策、计划或规划及其替代方案的环境影响进行正式的、系统的和综合的评价。欧洲战略环境影响评价的理论和实践在国际上具有领先的地位。本文介绍了战略环境影响评价的发展历程,特别对欧洲发达国家的战略环境影响评价的工作程序做了深入的分析,从战略的筛选、确定范围、环境影响评价、决策和批准、执行和监督、咨询与公众参与等方面,总结了欧洲战略环境影响评价的工作特点,对于中国战略环评工作的推动具有一定的借鉴意义。  相似文献   
810.
Journal of Material Cycles and Waste Management - Monolithic ceramic capacitors (MLCCs) contain a high level of silver. This paper describes a method to recover silver from the waste MLCCs. First,...  相似文献   
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