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排序方式: 共有437条查询结果,搜索用时 15 毫秒
1.
针对石化行业面源无组织排放VOCs难以准确定量的问题,建立了基于开路式傅里叶变换红外光谱技术(OP-FTIR)的面源污染源源强反演模型,并进行了现场模拟试验。试验结果表明,风向、风速、大气稳定度、监测距离、数据处理周期等都是影响反演模型准确性的重要灵敏度参数。以反演源强QP与实际排放量Q的比值(QP/Q)为量化指标,对各影响因素进行优化处理,确定了构建反演模型适用的边界条件。当各灵敏度参数稳定于适用边界条件之内时,QP/Q为0.85~0.90。 相似文献
2.
Christian Brandstätter David Laner Roman Prantl Johann Fellner 《Waste management (New York, N.Y.)》2014,34(12):2537-2547
Municipal solid waste landfills pose a threat on environment and human health, especially old landfills which lack facilities for collection and treatment of landfill gas and leachate. Consequently, missing information about emission flows prevent site-specific environmental risk assessments. To overcome this gap, the combination of waste sampling and analysis with statistical modeling is one option for estimating present and future emission potentials. Optimizing the tradeoff between investigation costs and reliable results requires knowledge about both: the number of samples to be taken and variables to be analyzed.This article aims to identify the optimized number of waste samples and variables in order to predict a larger set of variables. Therefore, we introduce a multivariate linear regression model and tested the applicability by usage of two case studies. Landfill A was used to set up and calibrate the model based on 50 waste samples and twelve variables. The calibrated model was applied to Landfill B including 36 waste samples and twelve variables with four predictor variables.The case study results are twofold: first, the reliable and accurate prediction of the twelve variables can be achieved with the knowledge of four predictor variables (Loi, EC, pH and Cl). For the second Landfill B, only ten full measurements would be needed for a reliable prediction of most response variables. The four predictor variables would exhibit comparably low analytical costs in comparison to the full set of measurements. This cost reduction could be used to increase the number of samples yielding an improved understanding of the spatial waste heterogeneity in landfills.Concluding, the future application of the developed model potentially improves the reliability of predicted emission potentials. The model could become a standard screening tool for old landfills if its applicability and reliability would be tested in additional case studies. 相似文献
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以制药工业综合废水处理为例对其采用的两级水解酸化复合好氧工艺的处理效果进行评估。按常规指标进行评估,该工艺对于制药综合废水的处理效果达到了设计目的,COD去除率可达到78.2%以上,NH+4-N的去除率达到99.3%,出水质量基本满足"污水综合排放标准(GB8978-1996)"二级标准和"辽宁省污水综合排放标准(DB21.1627-2008)";急性毒性的检测表明,经过该工艺处理后出水为低毒性;三维荧光谱分析(EEM)表明,制药综合废水经生物处理后的可溶性有机物中仍然存在难降解物质,建议增加物化处理以提高处理效果;并且制药废水经处理后的出水中的盐度对排入的生态系统存在风险,建议纳入排放标准以加强管理。 相似文献
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Mauro Mecozzi Demetria Cardarilli Eva Pietrantonio Marina Amici 《Chemistry and Ecology》2013,29(4):239-254
In this paper a method for the study of the qualitative similarity of extractable humic substance (EHS) in marine sediments based on the realisation of UV spectral library of EHS is described. the spectral library was built including the digitised spectra of humic substance extracted from several marine sediments (46 samples) and two samples of standard materials (lignin sulphonate and humic substance) in a Statistica data file. the data matrix was elaborated by means of different multivariate statistic techniques such as Cluster Analysis (CA), Principal Components Analysis (PCA) and the univariate technique Spectral Correlation Analysis (SCA). This approach allows us to show the contribution of different organic compounds (aromatic, lipid and acid) to the composition of EHS and moreover it evidences also the structural characteristics of EHS in terms of similarities in the qualitative composition of samples such as presence of terrestrial and/or vegetal contributions. the UV library is an objective tool to study the qualitative composition of EHS and it represents a complementary approach to the most common methods based on the application of spectroscopic (IR, 13CNMR), potentiometric and chromatographic techniques. 相似文献
8.
M. Hafidi G. Ait Baddi V. Gilard P. Ramos K. Alimi J. C. Revel 《Chemistry and Ecology》2013,29(4):313-324
Elemental analysis, fluorescence spectroscopy and differential scanning calorimetry (DSC) were applied to the study of fulvic acids isolated from different stages during olive mill waste composting. The fulvic extracted acids are characterized by a high nitrogen content and O/C ratio values that may result from the high degree of humification and the synthesis of more condensed humic complexes. This was confirmed by fluorescence spectroscopy in the synchronous-scan mode by the decrease of shoulder intensities at intermediate wavelengths indicating the increase of polycondensation and conjugation of unsaturated structures and the greater uniformity of fluorophores. Fluorescence spectra in the emission, excitation and synchronous modes became simpler with compost maturation. This was confirmed by DSC results which proved the high degree of polycondensation of aromatic nuclei of fulvic acid molecules during olive mill waste composting. 相似文献
9.
The production of neem oil coated urea (NOCU), a technology developed by the Indian Agricultural Research Institute, has been grown to over 2.0 million tons per year. The estimation of neem oil content in NOCU is important due to its significance in ensuring agronomic efficiency. Therefore, this study was taken up to develop a simple method for the determination of neem oil in NOCU. The procedure involves extraction of neem oil from NOCU; saponification of extracted oil; oxidation of released glycerol to formaldehyde, and subsequent conversion of formaldehyde to a dihydrolutidine derivative. Its concentration was determined spectrophotometrically. The recoveries of neem oil from NOCU with oil load of 500 and 1000?ppm were 87.6?±?3.0% and 90.0?±?4.8% respectively with direct method; and improved to 92.6?±?4.0% and 96.7?±?3.8% after including the in situ purification. A simple method based on the Hantzsch reaction was developed for the determination of neem oil in NOCU. This method is superior to earlier methods in terms of sensitivity, simplicity, and time required. 相似文献
10.
Susan Taylor David B. Ringelberg Katerina Dontsova Charles P. Daghlian Marianne E. Walsh Michael R. Walsh 《Chemosphere》2013
Two compounds, 2,4-dinitroanisole (DNAN) and 3-nitro-1,2,4-triazol-5-one (NTO) are the main ingredients in a suite of explosive formulations that are being, or soon will be, fielded at military training ranges. We aim to understand the dissolution characteristics of DNAN and NTO and three insensitive muntions (IM) formulations that contain them. This information is needed to accurately predict the environmental fate of IM constituents, some of which may be toxic to people and the environment. We used Raman spectroscopy to identify the different constituents in the IM formulations and micro computed tomography to image their three-dimensional structure. These are the first three-dimensional images of detonated explosive particles. 相似文献