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861.
在北京十三陵地震台建设了一个高度集成的地震观测监控系统,将原来分散的观测项目(如测震、GPS、气氡、气汞、电磁波、地电场等测项),改造为集中到一台服务器管理,在一个监控平台上统一实现了对台站数据的收集、入库、管理、处理、监控等业务;对这些观测项目可以在控制台上直接取数并将数据入库;初步实现了观测数据的收集、数据处理、数据管理、数据监控的软件管理系统,减少了系统维护工作量,方便台站工作人员操控。监控系统的地震前兆数据监管软件系统DataMonitor可准实时监视数据,检查数据的异常和到达情况,并向台站数据管理人员告警;可对数据库数据进行统计,包括数据到达情况统计、缺数统计、数据连续率统计等。该系统还提供多种前兆数据处理方法,实现对前兆数据的各种常规分析处理。 相似文献
862.
苏南典型河段磷的分布及释放特性研究 总被引:1,自引:0,他引:1
通过测定常州典型河段河水和底泥中的磷含量,同时分析了磷在不同底泥颗粒中含量分布的变化,阐述了河流中磷的分布和转移趋势。结果表明:河水中的磷含量通常低于底泥间隙水中的磷含量,但当河流发生富营养化后,底泥中的磷大量向上层水体释放,使得河水中的磷含量不断增加。底泥有效磷与总磷含量之间没有明显相关性,而与底泥间隙水的磷含量之间存在着交换平衡。底泥颗粒以2μm~50μm的粒级为主,即以细砂和粉砂质有机-无机聚合体矿物颗粒为主。磷在底泥颗粒中的含量随着底泥粒径的增大而减少,且粒径越大的颗粒对磷的吸附能力越弱,其中的磷向外释放的可能性越大。 相似文献
863.
Fang Fang Yan Yang Jinsong Guo Hong Zhou Chuan Fu Zhe Li 《Frontiers of Environmental Science & Engineering in China》2011,5(3):426-434
Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter
(DOM) in the water-level-fluctuation zone (WLFZ) of Kai County, Three Gorges Reservoir (TGR). Most of the soil DOM analyzed
in this study was found to contain four fluorescence peaks. Peaks A and C represent humic-like fluorescence, whereas peaks
B and D represent tryptophan-like fluorescence. Peaks E and F, which represent tyrosine-like fluorescence, only appeared in
certain soils. Soil humus was the main source of DOM in soil, and higher concentration of soil DOM was found in the exposed
soil than submerged soil. Compared to the peaks A and B, the fluorescence intensities of peaks C and D were strongly influenced
by the fluctuating water level. Analysis of fluorescence intensities of different peaks in soil DOM showed that WLFZ soil
was not contaminated significantly. Soil DOM contained at least two types of humic-like fluorescence groups and two types
of protein-like fluorescence groups. The proportion of the content of peak A in soil organic matter was quite stable. The
soil DOM in exposed soil had relatively high humification and aromaticity, and periodic submerging and exposure of soil had
an impact on the humification of soil DOM. 相似文献
864.
絮凝条件对絮体分形结构的影响 总被引:17,自引:3,他引:17
在85kg/m3的含沙高浊水中投加阳离子高分子聚合物,借助图像分析技术与沉降技术分析探讨了不同絮凝条件下泥沙絮凝形态学参数:絮体粒径、絮体有效质量密度、絮体自由沉速、浑液面沉速与上清液余浊等的变化规律.利用表征参数“分维”定量控制不同絮凝条件(如搅拌速率、搅拌时间、高分子浓度等)对含沙高浊水絮体结构分形特性的影响.实验证明,不合适的絮凝条件将导致絮体分形构造疏松脆弱,分维值低.絮凝条件合适时(快速絮凝强度为:r1=300r/min,t1=10s;慢速絮凝强度:r2=120r/min,t2=180s;CP浓度:0.1%),絮体分形结构处于最佳状态.该状态下的絮体具有粒径较大、沉速快、有效质量密度高、粒度分布均匀,分维值最高(D3=2.16)的特点.而且,由静沉实验测得浑液面沉速高,上清液余浊也低.泥沙絮体分形结构达最佳时的混凝性能、沉降性能与结构密实性均较理想. 相似文献
865.
三峡库区小城镇水环境与工业产业结构优化模型——以万州区分水镇为例 总被引:2,自引:0,他引:2
以长江上游三峡库区腹部的重庆市万州区分水镇为研究对象,根据2005年分水镇工业各行业的结构特点及各行业对水环境的污染特点,建立水环境--经济工业结构多目标优化模型,选取工业生产总值最大和COD排放量最小作为优化目标,量化分水镇2010年工业结构,选择出符合当地经济发展"十一五"规划目标和水环境保护目标的工业结构优化方案,提出具体的工业产业发展建议,达到减少工业污染物对境内长江次级河流瀼渡河的污染,有效地改善瀼渡河水质状况,同时保证分水镇社会、经济、水环境的可持续发展的目的.文章同时也对三峡库区小城镇的工业产业结构优化调整,获得既符合经济发展目标又满足水环境保护要求的合理的工业产业结构,提供可借鉴的思路和方法. 相似文献
866.
867.
868.
活性污泥中PFU原生动物群落的作用和意义 总被引:1,自引:0,他引:1
原生动物是水生生态系统食物链中重要环节,发挥着十分重要的生态功能作用.在水环境质量变化评价与发展趋势预测中,在水质监测应用方面,PFU原生动物群落显示了其它较高等生物类群无法比拟的很多优点.文章阐述了活性污泥中PFU原生动物群落的特征,重点介绍了活性污泥中PFU原生动物的应用,同时指出了应用中该注意的问题. 相似文献
869.
It is widely accepted that urban plant leaves can capture airborne particles. Previous studies on the particle capture capacity of plant leaves have mostly focused on particle mass and/or size distribution. Fewer studies, however, have examined the particle density, and the size and shape characteristics of particles, which may have important implications for evaluating the particle capture efficiency of plants, and identifying the particle sources. In addition, the role of different vegetation types is as yet unclear. Here, we chose three species of different vegetation types, and firstly applied an object-based classification approach to automatically identify the particles from scanning electron microscope(SEM)micrographs. We then quantified the particle capture efficiency, and the major sources of particles were identified. We found(1) Rosa xanthina Lindl(shrub species) had greater retention efficiency than Broussonetia papyrifera(broadleaf species) and Pinus bungeana Zucc.(coniferous species), in terms of particle number and particle area cover.(2) 97.9% of the identified particles had diameter ≤10 μm, and 67.1% of them had diameter ≤2.5 μm. 89.8% of the particles had smooth boundaries, with 23.4% of them being nearly spherical.(3) 32.4%–74.1% of the particles were generated from bare soil and construction activities, and 15.5%–23.0% were mainly from vehicle exhaust and cooking fumes. 相似文献
870.
Da Sheng Lingjun Bu Shumin Zhu Yangtao Wu Jue Wang Nan Li Shiqing Zhou 《环境科学学报(英文版)》2022,34(7):21-27
Pre-oxidation has been reported to be an effective way to remove algal cells in water, but the released algal organic matter (AOM) could be oxidized and lead to the increment in disinfection by-product (DBP) formation. The relationship between pre-oxidation and AOM-derived DBP formation needs to be approached more precisely. This study compared the impact of four pre-oxidants, ozone (O3), chlorine dioxide (ClO2), potassium permanganate (KMnO4) and sodium hypochlorite (NaClO), on the formation of nitrogenous (N-) and carbonaceous (C-) DBPs in AOM chlorination. The characterization (fluorescent properties, molecular weight distribution and amino acids concentration) on AOM samples showed that the characterization properties variations after pre-oxidation were highly dependent on the oxidizing ability of oxidants. The disinfection experiments showed that O3 increased DBP formation most significantly, which was consistent with the result of characterization properties variations. Then canonical correspondent analysis (CCA) and Pearson's correlation analysis were conducted based on the characterization data and DBP formation. CCA indicated that C-DBPs formation was highly dependent on fluorescent data. The formation of haloacetic acids (HAAs) had a positive correlation with aromatic protein-like component while trichloromethane (TCM) had a positive correlation with fulvic acid-like component. Pearson's correlation analysis showed that low molecular weight fractions were favorable to form N-DBPs. Therefore, characterization data could provide the advantages in the control of DBP formation, which further revealed that KMnO4 and ClO2 were better options for removing algal cells as well as limiting DBP formation. 相似文献