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Composition analysis of colored dissolved organic matter in Taihu Lake based on three dimension excitation-emission fuorescence matrix and PARAFAC model, and the potential application in water quality monitoring

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Journal of Environmental Sciences 2007年第7期19卷 787-791页

作者： WANG Zhi-gang LIU Wen-qing ZHAO Nan-jing LI Hong-bin ZHANG Yu-jun SI-MA Wei-cang LIU Jian-guo School of Earth and Space Science University of Science and Technology of China Hefei 230026 China. Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China

Taihu Lake is one of the five biggest lakes in China. Surface water samples from 26 sampling sites of Taihu Lake were collected. Furthermore wet chemical analysis （CODCr and BOD5） and measurement of three dimensional excitation-emission matrix （3DEEM） spectra in the laboratory have been conducted. Using parallel factor analysis （PARAFAC） model, three components of colored dissolved organic matter （CDOM） have been identified successfully, based on the analysis of 3DEEM data. The characteristics of the three components also have been described by comparing them to some components of CDOM, identified in earlier researches. Meanwhile, spatial variations of concentration for the three components in Taihu Lake have been analyzed, and the result indicates that the concentration of component 1 depends more on the situation of wastewater pollution and can be used as the indicator of wastewater pollution. The relationship between the concentrations of the three components and results of the wet chemical analysis show that none of the three components can be used as indicators of gross organic matter in water. However, the concentrations of all the three components have obvious linear relationships with the BOD5 value, especially for component 1 （r = 0.72878）. Finally, the potential applications of the composition analysis based on 3DEEM and PARAFAC model in water quality monitoring have been illuminated.

关键词： 3DEEM Taihu Lake monitoring of water quality CDOM PARAFAC

Water-soluble brown carbon in atmospheric aerosols from the resource-dependent cities:Optical properties,chemical compositions and sources

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Journal of Environmental Sciences 2024年第4期138卷 74-87页

作者： Haoji Wang Yue Su Yangzheng Liu Fei Xie Xingjun Zhou Ruihong Yu Changwei Lü Jiang He School of Ecology and Environment Inner Mongolia UniversityHohhot 010021China Institute of Environmental Geology Inner Mongolia UniversityHohhot 010021China Environmental Monitoring Center of Inner Mongolia Hohhot 010011China

As a vital type of light-absorbing aerosol,brown carbon(BrC)presents inherent associations with atmospheric photochemistry and climate change.However,the understanding of the chemical and optical properties of BrC is limited,especially in some resource-dependent cities with long heating periods in northwest China.This study showed that the annual average abundances of Water-soluble BrC(WS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and Wuhai and the concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency(MAE365)of WS-BrC presented significant seasonal patterns,with high values in the heating season and low values in the non-heating season;while showing opposite seasonal trends for the Absorption Angstr?m exponent(AAE_(300-400)).Comparatively,the levels of WS-BrC in developing regions(such as cities in Asia)were higher than those in developed regions(such as cities in Europe and Australia),indicating the significant differences in energy consumption in these regions.By combining fluorescence excitation-emission matrix(EEM)spectra with the parallel factor(PARAFAC)model,humic-like(C1 and C2)and proteinlike(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at Wuhai,respectively.The results of source apportionment suggested that the potential source regions of WS-BrC varied in heating vs.non-heating seasons and that the properties of WS-BrC significantly depended on primary emissions(e.g.,combustion emissions)and secondary formation.

关键词： Water-soluble brown carbon Atmospheric aerosols Optical properties PARAFAC Source apportionment

Changes of DOM and its correlation with internal nutrient release during cyanobacterial growth and decline in Lake Chaohu, China

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Journal of Environmental Sciences 2023年第2期124卷 769-781页

作者： Yan Bao Tao Huang Chengwu Ning Tingting Sun Pengliang Tao Jie Wang Qingye Sun School of Resources and Environmental Engineering Anhui UniversityHefei 230601China Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration Anhui UniversityHefei 230601China

The seasonal changes in dissolved organic matter(DOM),and its correlation with the release of internal nutrients during the annual cycle of cyanobacteria in the eutrophic Lake Chaohu,China,were investigated from four sampling periods between November 2020 and July 2021.The DOM fluorescence components were identified as protein-like C1,microbial humic-like C2,and terrestrial humic-like C3.The highest total fluorescence intensity(FT)of DOM in sediments during the incubation stage is due to the decomposition and degradation of cyanobacteria remains.The lowest humification of DOM and the highest proportion of C1 in waters during the initial cyanobacterial growth indicate that fresh algae are the main source.The highest molecular weight of DOM and FT of the C2 in sediments during cyanobacterial outbreaks indicate the concurrent deposition of undegraded cyanobacterial remains and microbial degradation.The components of DOM are affected mainly by the dissolved total phosphorus in waters,while the temperature drives the annual cycle of cyanobacteria.The decreasing C1 in sediments and increasing nutrients in waters from the cyanobacterial incubation to outbreak indicate that mineralization of algal organic matter contributes importantly to the release of internal nutrients,with the strongest release of phosphorus observed during the early growth of cyanobacteria.The humic-like C2 and C3 components could also affect the dynamics of internal phosphorus through the formation of organic colloids and organic–inorganic ligands.The results show that the degradation of DOM leads to nutrients release and thus supports the continuous growth of cyanobacteria in eutrophic Lake Chaohu.

关键词： Eutrophication Shallow lake Sediment-water interface Algal blooms Fluorescence components PARAFAC

A simple guideline to apply excitation-emission matrix spectroscopy(EEMs)for the characterization of dissolved organic matter(DOM)in anoxic marine sediments

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Acta Oceanologica Sinica 2023年第1期42卷 109-119页

作者： Shuchai Gan Verena BHeuer Frauke Schmidt Lars Wörmer Kai-Uwe Hinrichs MARUM—Center for Marine Environmental Sciences University of BremenBremenD-28359Germany

Marine sediments represent a major carbon reservoir on Earth.Dissolved organic matter(DOM)in pore waters accumulates products and intermediates of carbon cycling in sediments.The application of excitation-emission matrix spectroscopy(EEMs)in the analysis of subseafloor DOM samples is largely unexplored due to the redox-sensitive matrix of anoxic pore water.Therefore,this study aims to investigate the interference caused by the matrix on EEMs and propose a guideline to prepare pore water samples from anoxic marine sediments.The parameters determined by fluorescence spectra include 3D-index derived from EEMs after parallel factor analysis(PARAFAC),fluorescence index(FI)(contribution of terrigenous DOM),biological index(BIX)and humification index(HIX)derived from 2D emission spectra.First,we investigated the impacts of extensively-presented ions as typical electron acceptors,which are utilized by anaerobic microbes and stratified in marine sediments:Fe(II),Fe(III),Mn(II)and sulfide in anoxic pore water resulted in biases of fluorescent signals.We proposed threshold concentrations of these ions when the interference on EEMs occurred.Effective removal of sulfide from sulfide-rich samples could be achieved by flushing with N_(2)for 2 min.Second,the tests based on DOM standard were further verified using pristine samples from marine sediments.There was a significant change in the fluorescence spectra of DOM in anoxic sediments from the Rhône Delta.This study demonstrated that the change was caused by oxidation of the matrix rather than the intrinsic alteration of DOM.It was confirmed by extracted DOM via both EEMs analysis and Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).Slight oxidation of sulfur-containing compounds(e.g.,sulfhydryl)and polyphenol-like compounds occurred.Finally,a sample preparation sequence is proposed for pore water from anoxic sediments.This method enables measurement with small volumes of the sample(e.g.,50µL in this study)and ensures reliable data without the interference

关键词： marine subsurface sediment EEMs PARAFAC FT-ICR-MS anaerobic pore water

滇池流域表层沉积物溶解性有机质分布特征及其环境意义

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环境科学学报 2024年

作者：吕睿赵好轩麦富生杨健王金鹏杨传玺邢俊峰王乾肖宜华青岛理工大学环境与市政工程学院生态环境部华南环境科学研究所国家环境保护水环境模拟与污染控制重点实验室

以滇池流域表层沉积物为研究对象，利用碳氮同位素和光谱学等分析方法探究滇池流域表层沉积物的理化性质及溶解性有机质（DOM）组成特征.结果表明：滇池湖中心表层沉积物中溶解态有机碳（DOC）含量明显高于湖岸带与河流，说明滇池表层... 详细信息

以滇池流域表层沉积物为研究对象，利用碳氮同位素和光谱学等分析方法探究滇池流域表层沉积物的理化性质及溶解性有机质（DOM）组成特征.结果表明：滇池湖中心表层沉积物中溶解态有机碳（DOC）含量明显高于湖岸带与河流，说明滇池表层沉积物DOC主要来源于湖中本地有机碳的积累；δ13C同位素结果证实滇池沉积物DOC主要为自生源.紫外-可见吸收光谱结果表明滇池表层沉积物中有色溶解性有机质（CDOM）的含量呈现出从湖中心向湖岸带和河流逐渐递减的趋势，但是湖中心表层沉积物CDOM分子的芳香性和分子量低于河流与湖岸带，说明浮游植物初级生产是滇池流域表层沉积物有机质的重要来源.三维荧光光谱耦合平行因子分析（EEM-PARAFAC）模型解析出滇池流域表层沉积物DOM 3种荧光组分：自生源类腐殖质组分C1(Ex/Em=240/414 nm)，类蛋白组分C2(Ex/Em=270/320 nm)和陆源类腐殖质组分C3(Ex/Em=270/506 nm).受人为活动干扰大的滇池东部位点DOM荧光强度显著高于西部湖滨带和河流位点.微生物活动来源类腐殖质C1组分在所有点位均占有较高的比例，说明滇池表层沉积物具有较高的微生物活性.综上，富营养化引起浮游植物的初级生产是滇池湖中表层沉积物DOC的主要来源，强烈的微生物活动和外源人为活动能够增强滇池表层沉积物DOM的积累和转化.滇池表层沉积物较高浓度的碳、氮和磷等生源要素可以通过沉积物再悬浮释放到上覆水中，造成水体的二次污染.研究结果可为滇池水环境保护与治理提供基础数据.

关键词：溶解性有机质滇池表层沉积物紫外-可见吸收光谱三维荧光光谱 PARAFAC

Insight into removal of dissolved organic matter in post pharmaceutical wastewater by coagulation-UV/H_2O_2

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Journal of Environmental Sciences 2019年第2期31卷 329-338页

作者： Feng Qian Mengchang He Jieyun Wu Huibing Yu Liang Duan State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences

The removal of four dissolved organic matter(DOM) fractions, non-acid hydrophobics,hydrophobic acids, hydrophilics and transphilics, was achieved by coagulation-UV/H_2O_2 oxidation in post-pharmaceutical wastewater(PhW W). Coagulation with Polyferric chloride(PFC), Polymeric ferric sulfate(PFS) and Polymeric aluminum ferric chloride(PAFC) was studied separately to evaluate the effects of the initial pH and coagulant dosage. The coagulation-UV/H_2O_2 oxidation method resulted in much higher reduction rates for dissolved organic carbon(DOC)(by 75%) and UV_(254)(by 92%) than coagulation or UV/H_2O_2 oxidation alone. The proportion of non-acid hydrophobics, hydrophobic acids, transphilics and hydrophilics removed by coagulation was 54%, 49%, 27% and 12 %, while the combined treatment removed 92%, 87%,70% and 39%, respectively. Parallel factor analysis(PARAFAC) of fluorescence measurements revealed that the humic-like fluorescent component C4 showed the highest removal(by 44%)during the coagulation stage. After coagulation-UV/H_2O_2 treatment, the humic-like fluorescent component C3 had the highest removal(by 72%), whereas xenobiotic organic fluorescent components C1 and C4 remained recalcitrant to decomposition. Significant correlations(R2> 0.8)between C1 and the hydrophobic acids and non-acid hydrophobics suggested the possibility of using fluorescence spectroscopy as an effective tool to assess variations in DOM fraction treatment efficacy in coagulation-UV/H_2O_2 systems. After the combined treatment, toxic inhibition of cellular activity by post PhW W decreased from 88% to 47% and biodegradability increased from 0.1 to 0.52.

关键词： Post PhWW Coagulation UV/H2O2 PARAFAC DOM fractionation Toxicity

无机-有机综合指标在煤层顶板涌水水源判别中的应用

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煤矿安全 2023年第12期54卷 182-190页

作者：孙钧青王皓杨建尚宏波王甜甜乔伟煤炭科学研究总院北京100013 中煤科工西安研究院(集团)有限公司陕西西安710077 陕西省煤矿水害防治技术重点实验室陕西西安710077

常规的无机水化学参数较难判别某些井田中成分相近的煤层顶板涌水水源,针对该问题,以榆横矿区某井田为研究区,在K^(+)+Na^(+)、Ca^(2+)、Mg^(2+)、Cl^(−)、SO_(4)^(2−)、HCO_(3)^(−)、TDS(总溶解固体)等无机指标的基础上加入TOC(总有机... 详细信息

常规的无机水化学参数较难判别某些井田中成分相近的煤层顶板涌水水源,针对该问题,以榆横矿区某井田为研究区,在K^(+)+Na^(+)、Ca^(2+)、Mg^(2+)、Cl^(−)、SO_(4)^(2−)、HCO_(3)^(−)、TDS(总溶解固体)等无机指标的基础上加入TOC(总有机碳)、UV254(紫外吸光度)、DOM(溶解性有机质)等有机指标,探究无机-有机综合指标在煤层顶板涌水水源判别中的作用;利用荧光指纹技术和PARAFAC得到DOM主要组分及荧光强度,在对水样的无机、无机-有机数据集进行主成分分析(PCA)后,使用随机森林算法(RF)分别构建无机指标判别模型和无机-有机综合指标判别模型;并对8个待测水样的类型也进行了正确的判别。结果表明:综合判别模型的性能总是优于无机判别模型;在综合模型下,RF算法的平均精度、平均查准率、平均召回率和f1调和指数分别达到了93.14%、94.79%、95.08%、93.73%,较无机模型分别提高了9.71%、11.84%、12.25%、11.5%,回代准确率为98.63%;无机-有机综合指标能够显著提高煤层顶板涌水水源判别准确率。

关键词：水源判别有机荧光指纹 PARAFAC PCA RF

基于张量数据模型的声矢量传感器阵列信号方位估计算法研究

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基于张量数据模型的声矢量传感器阵列信号方位估计算法研究

作者：沈丽伟哈尔滨工程大学

学位级别：硕士

传统的声矢量传感器阵列信号处理算法将获得的信号展开成矩阵或长矢量形式,破坏了声矢量传感器阵列获得信息的多维结构特点,为解决此问题,本文选择高维数据运算领域的代表方法——张量作为数据的表达形式,从张量数据模型角度出发,研究... 详细信息

传统的声矢量传感器阵列信号处理算法将获得的信号展开成矩阵或长矢量形式,破坏了声矢量传感器阵列获得信息的多维结构特点,为解决此问题,本文选择高维数据运算领域的代表方法——张量作为数据的表达形式,从张量数据模型角度出发,研究基于张量数据模型的声矢量传感器阵列信号方位估计算法,使得获得声源信息中的多维结构信息能够被充分利用,从而达到提高方位估计算法精度的目的。本文首先对张量数据模型与常规多重信号分类(MUSIC)算法和旋转不变子空间(ESPRIT)算法的融合进行研究,得到基于张量数据模型的MUSIC算法和ESPRIT算法,相较于常规MUSIC算法和ESPRIT算法而言,经张量数据模型改进后的算法具有估计精度更高的优势,但因计算过程从低维拓展到高维,同时也带来计算复杂度过高的问题。针对基于张量数据模型的MUSIC算法因数据模型维度拓展,需要更高维度的谱峰搜索,从而导致算法计算量庞大,基于张量数据模型的ESPRIT算法无法自动匹配二维方位估计结果的问题,本文继而对基于自协方差张量模型平行因子(PARAFAC)分解的DOA估计算法进行研究。通过分析可知,该算法虽无需上文中提到的高维谱峰搜索和参数配对过程,但存在低信噪比下进行PARAFAC分解时易陷入局部最优解从而导致方位估计失效的问题。针对基于自协方差张量模型PARAFAC分解的DOA估计算法低信噪比下估计失效的问题,本文相继对基于张量数据模型直接三线性PARAFAC分解的DOA估计算法和基于张量数据模型快速PARAFAC分解的DOA估计算法进行研究。上述两种算法利用不同的方法对因子矩阵进行初始估计,从而避免因随机初始化因子矩阵导致PARAFAC分解结果陷入局部最优解的问题,且后者相较于本文中研究的其他基于张量数据模型处理的相应算法可大幅降低计算复杂度,经仿真分析和外场试验数据处理证实这两种算法相关理论分析的正确性。

关键词：声矢量传感器阵列张量模型 PARAFAC DOA

Rapid and simple analysis of amphetamine-type illegal drugs using excitation–emission matrix fluorescence coupled with parallel factor analysis

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Forensic Sciences Research 2019年第2期4卷 179-187页

作者： Buyi Xu Yi Ye Linchuan Liao Sichuan Provincial Department of Public Security ChengduChina Department of Forensic Toxicological Analysis West China School of Preclinical and Forensic MedicineSichuan UniversityChengduChina

Nowadays,the abuse of illegal drugs has been an increasingly grim problem in the world.Excitation–emission matrix fluorescence combined with parallel factor analysis was used to make a quantitative analysis of the simulated amphetamine-type illegal drugs.Satisfactory results were achieved for simultaneous determination of methamphetamine(MAM)and 3,4-methylenedioxymethamphetamine(MDMA)in the presence of adulterants.The average recoveries were(99.8±0.6)%and(101.6±5.7)%for MAM and MDMA,respectively.Figures of merit including root-mean-square error of calibration and prediction,sensitivity and selectivity were investigated to evaluate the performance of the proposed method.The limits of detection were 0.054 and 0.0021 g/mL for MAM and MDMA,respectively.

关键词： Forensic science illegal drugs excitation–emission matrix fluorescence PARAFAC