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411.
飞信通讯手段在突发环境污染事件处置时的应用   总被引:1,自引:0,他引:1  
对现有移动通讯方式在突发环境污染事件中的应用进行了比较。通过实例,简述了飞信作为突发环境污染事件应急处置时通讯方式的应用。结果表明,飞信综合了一对一、多对多的语音和图文信息传输方式,在技术资料支持和监测结果通报方面具有明显的实用价值,配合防爆型对讲机,可以满足应对突发环境污染事件时对通讯的要求。  相似文献   
412.
介绍了国家重大科学仪器设备开发专项"基于质谱技术的全组分痕量重金属分析仪器开发和应用示范"项目在电感耦合等离子体质谱仪(ICP-MS)研发、低温等离子体样品引入ICP-MS联用系统、ICP-MS监测汞的采样与预处理等方面的研究进展,并对ICP-MS应用发展及产业化前景进行了展望。  相似文献   
413.
Sources, partitioning and toxicological risk of 15 priority polycyclic aromatic hydrocarbons (PAHs) in surface sediments from drinking water sources of Taihu Lake, with an area of 2428 km(2) located in the most developed and populated area of China, were studied, and the results were compared with those in other lakes of China and the USA. Concentrations of the 15 PAHs in sediments ranged from 436.6 to 1334.9 ng g(-1) (dw). Gasoline combustion, coal combustion, diesel combustion from shipping and spillage of petroleum were apportioned to be the main sources of PAHs in this area by principal component analysis, which contributed 35.19%, 26.43%, 25.41% and 12.97% to the PAH sources estimated by further multiple linear regression. Levels of PAHs in sediments were negatively correlated with contents of clay and fine silt (<16 μm), while positively with contents of medium silt, coarse silt and sand (>16 μm). Humin with size larger than 16 μm contained the largest part of the burden of PAHs in sediments, but the specific partitioning domain (bound humic acid, lipid or insoluble residue) depended on properties of organic matter reflected by optical absorbance at 465 and 665 nm. Total toxic benzo[a]pyrene equivalent (TEQ(carc)) of the carcinogenic PAHs in sediments varied from 31.8 to 209.3 ngTEQ(carc) g(-1). Benzo[a]pyrene and dibenzo[a,h]anthracene contributed 45.36 and 25.31% to total TEQ(carc), posing high toxicological risk to this area.  相似文献   
414.
The Three-North Shelter Forest Program is the largest afforestation reconstruction project in the world. Remote sensing is a crucial tool to map land use and land cover change, but it is still challenging to accurately quantify the change in forest extent from time-series satellite images. In this paper, 30 Landsat MSS/TM/ETM+ epochs from 1974 to 2012 were collected, and the high-quality ground surface reflectance (GSR) time-series images were processed by integrating the 6S atmosphere transfer model and a relative reflectance normalization algorithm. Subsequently, we developed a vegetation change tracking method to reconstruct the forest change history (afforestation and deforestation) from the time-series Landsat GSR images based on the integrated forest z-score (IFZ) model by Huang et al. (2009a), which was improved by multi-phenological IFZ models and the smoothing processing of IFZ data for afforestation mapping. The mapping result showed a large increase in the extent of forest, from 380,394 ha (14.8 % of total district area) in 1974 to 1,128,380 ha (43.9 %) in 2010. Finally, the land cover and forest change map was validated with an overall accuracy of 89.1 % and a kappa coefficient of 0.858. The forest change time was also successfully retrieved, with 22.2 % and 86.5 % of the change pixels attributed to the correct epoch and within three epochs, respectively. The results confirmed a great achievement of the ecological revegetation projects in Yulin district over the last 40 years and also illustrated the potential of the time-series of Landsat images for detecting forest changes and estimating tree age for the artificial forest in a semi-arid zone strongly influenced by human activities.  相似文献   
415.
Extracellular polymeric substances (EPS) were extracted from Aspergillus fumigatus using cationic exchange resin technique. The EPS were mainly composed of polysaccharide and low quantities of protein and nucleic acid. Biosorption of Cd(II), Pb(II), and Cu(II) of EPS was investigated as a function of pH using differential pulse polarography and the Ruzic model. Results showed that the EPS biosorption capacity determined using either the direct titration curves i?=?f(C M) or the method proposed by Ruzic (Analytica Chimica Acta 140:99–113, 1982) were coincident. Cu(II) had the highest affinity with EPS followed by Pb(II) and Cd(II). The total number of binding sites for Cu(II) and Cd(II) increased with pH in the range of 4.0–7.0. Similar trend was observed for Pb(II) at pH?4.0–5.0, while precipitates were observed at pH?6.0 and 7.0. The conditional binding constants of these three metals displayed low levels of fluctuation with pH and ranged from 4.02?±?0.02 to 5.54?±?0.05.  相似文献   
416.
The dynamic and residues of florasulam and flumetsulam in corn field ecosystem were investigated using quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The limits of quantification (LOQs) of the proposed method ranged from 0.005 to 0.01 mg/kg. Mean recoveries and relative standard deviations (RSDs) of the two compounds in all samples at three spiking levels ranged 94–110 % and 2.0–9.2 %, respectively. Florasulam and flumetsulam degradation followed first-order kinetics with half-lives 1.7–2.9 and 3.3–8.7 days in soil and 1.3–1.8 and 0.9–1.7 days in plant, respectively. The residues in all the samples were found to be less than the LOQs at preharvest intervals of 53 and 78 days. The results suggest that the combined use of florasulam and flumetsulam on corn is considered to be safe under the recommended conditions and can be utilized for establishing the maximum residue limit (MRL) of florasulam in corn in China.  相似文献   
417.
建立了Supelclean ENVI-Chrom P柱固相萃取-高效液相色谱法测定废水中11种酚类化合物的分析方法,并对固相萃取条件和液相色谱条件进行了讨论。该方法分离效果良好,净化效果明显,方法检出限为2×10-3~2×10-2mg/L,平行分析(n=6)的RSD为2.7%~16.4%,废水加标回收率除2,4-二硝基酚偏低以外,其他化合物的回收率为61.4%~115.8%。  相似文献   
418.
建立了以固相萃取为前处理条件,用液相色谱法测定水中10种硝基苯酚类化合物的分析方法。实验使用HLB(6 L/150 g)固相萃取柱富集水样中的目标化合物,二氯甲烷与乙酸乙酯体积比1:2的混合溶剂洗脱,采用Phenyl柱(4.6 mm×250 mm,5 μm)分离目标化合物,以乙腈(1%甲酸)/水(1%甲酸)为流动相进行梯度洗脱,二极管阵列检测器检测。10种硝基苯酚类物质在0.02~10 mg/L范围内呈现良好的线性。方法检出限为0.1~0.3 μg/L,水样加标相对标准偏差为5.19%~18.2%,平均加标回收率为49.8%~124%。该方法适用于水中10种硝基苯酚类化合物的测定。  相似文献   
419.
通过对我国辐射环境监测相关法规的调研,在深入分析当前辐射环境监测法规框架结构和突出问题的基础上,构建我国辐射环境监测法规体系,重点关注辐射环境质量监测、核与辐射监督性监测及应急监测等方面的工作需求,提出完善部门规章、健全核安全导则及规范性文件的建议。  相似文献   
420.
Both the net primary productivity (NPP) and the normalized difference vegetation index (NDVI) are commonly used as indicators to characterize vegetation vigor, and NDVI has been used as a surrogate estimator of NPP in some cases. To evaluate the reliability of such surrogation, here we examined the quantitative difference between NPP and NDVI in their outcomes of vegetation vigor assessment at a landscape scale. Using Landsat ETM+ data and a process model, the Boreal Ecosystem Productivity Simulator, NPP distribution was mapped at a resolution of 90 m, and total NDVI during the growing season was calculated in Heihe River Basin, Northwest China in 2002. The results from a comparison between the NPP and NDVI classification maps show that there existed a substantial difference in terms of both area and spatial distribution between the assessment outcomes of these two indicators, despite that they are strongly correlated. The degree of difference can be influenced by assessment schemes, as well as the type of vegetation and ecozone. Overall, NDVI is not a good surrogate of NPP as the indicators of vegetation vigor assessment in the study area. Nonetheless, NDVI could serve as a fairish surrogate indicator under the condition that the target region has low vegetation cover and the assessment has relatively coarse classification schemes (i.e., the class number is small). It is suggested that the use of NPP and NDVI should be carefully selected in landscape assessment. Their differences need to be further evaluated across geographic areas and biomes.  相似文献   
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