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Simulated photo-degradation of dissolved organic matter in lakes revealed by three-dimensional excitation-emission matrix with regional integration and parallel factor analysis

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Journal of Environmental Sciences 2020年第4期32卷 310-320页

作者： Jin Zhang Fanhao Song Tingting Li Kefu Xie Huiying Yao Baoshan Xing Zhongyu Li Yingchen Bai School of Environmental and Safety Engineering Changzhou UniversityJiangsu 213164China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Water Sciences Beijing Normal UniversityBeijing 100875China Department of Chemistry Beijing Normal UniversityBeijing 100875China Stockbridge School of Agriculture University of MassachusettsAmherstMA01003USA

Simulated photo-degradation of fluorescent dissolved organic matter(FDOM) in Lake Baihua(BH) and Lake Hongfeng(HF) was investigated with three-dimensional excitationemission matrix(3 DEEM) fluorescence combined with the fluorescence regional integration(FRI),parallel factor(PARAFAC) analysis,and multi-order kinetic *** the FRI analysis,fulvic-like and humic-like materials were the main constituents for both BH-FDOM and *** individual components were identified by use of PARAFAC analysis as humic-like components(C1),fulvic-like components(C2),protein-like components(C3) and unidentified components(C4).The maximum 3 DEEM fluorescence intensity of PARAFAC components C1-C3 decreased by about 60%,70% and 90%,respectively after *** multi-order kinetic model was acceptable to represent the photo-degradation of FDOM with correlation coefficient(Radj2)(0.963-0.998).The photo-degradation rate constants(kn) showed differences of three orders of magnitude,from 1.09 × 10-6 to 4.02 × 10-4 min-1,and half-life of multi-order model(T1/2n)ranged from 5.26 to 64.01 *** decreased values of fluorescence index(FI) and biogenic index(BI),the fact that of percent fluorescence response parameter of Region I(PⅠ,n) showed the greatest change ratio,followed by percent fluorescence response parameter of Region II(PⅡ,n,while the largest decrease ratio was found for C3 components,and the lowest T1/2n was observed for C3,indicated preferential degradation of protein-like materials/components derived from biological sources during *** research on the degradation of FDOM by 3 DEEM/FRI-PARAFAC would be beneficial to understanding the photo-degradation of FD OM in natural environments and accurately predicting the environmental behaviors of contaminants in the presence of FDOM.

关键词： Fluorescent dissolved organic matter Photo-degradation Fluorescence regional integration parallel factor analysis Three-dimensional excitationemission matrix Multi-order kinetic models

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Blind spatial signature estimation via time-varying user power loading and parallel factor analysis

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2005年第5期53卷 1697-1710页

作者： Rong, Y Vorobyov, SA Gershman, AB Sidiropoulos, ND Univ Duisburg Essen Dept Commun Syst D-47057 Duisburg Germany Tech Univ Crete Dept Elect & Comp Engn Khania 73100 Greece Univ Minnesota Dept Elect & Comp Engn Minneapolis MN 55455 USA

In this paper, the problem of blind spatial signature estimation using the parallel factor (PARAFAC) analysis model is addressed in application to wireless. communications. A time-varying user power loading in the uplink mode is proposed to make the model identifiable and to enable application of PARAFAC analysis. Then, identifiability issues are studied in detail and closed-form expressions for the corresponding modified Cramer-Rao bound (CRB) are obtained. Furthermore, two blind spatial signature estimation algorithms are developed. The first technique is based on the PARAFAC fitting trilinear alternating least squares (TALS) regression procedure, whereas the second one makes use of the joint approximate diagonalization algorithm. These techniques do not require any knowledge of the propagation channel and/or sensor array manifold and are applicable to a more general class of scenarios than earlier approaches to blind spatial signature estimation.

关键词： blind spatial signature estimation parallel factor analysis sensor array processing

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Assessing the dynamics of chromophoric dissolved organic matter in a subtropical estuary using parallel factor analysis

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MARINE CHEMISTRY 2011年第1-4期124卷 125-133页

作者： Guo, Weidong Yang, Liyang Hong, Huasheng Stedmon, Colin A. Wang, Fuli Xu, Jing Xie, Yuyuan Xiamen Univ State Key Lab Marine Environm Sci Xiamen 361005 Fujian Peoples R China Aarhus Univ Dept Marine Ecol Natl Environm Res Inst DK-4000 Roskilde Denmark

The spatial and temporal dynamics of chromophoric dissolved organic matter (CDOM) were studied using excitation emission matrix fluorescence spectroscopy (EEMs) and parallel factor analysis (PARAFAC) during five cruises in the subtropical Jiulong Estuary from August 2008 to June 2009. Two humic-like (Cl and C3), one tryptophan-like (C4) and one possible protein-like (C2) component was identified by PARAFAC and their behavior in the river-estuary-coastal interface was evaluated. The spatial distributions of the maximum fluorescence (F(max)) for the fluorescent components showed a remarkable loss in the upper estuary. The following significant addition of all components in the low salinity turbidity maximum zone suggested the inputs from riverine source, sediment resuspension and the surrounding mangrove ecosystem. Cl, C2 and C3 showed conservative behavior in the middle and lower estuary indicated by the linear relationship between their fluorescence intensities and salinity in the five cruises. However, the tryptophan-like C4 received widespread additions (likely from autochthonous production) in the estuary. Although the humic-like Cl and C3 showed no significant variation in the estuary-coastal interface, C2 and C4 decreased more rapidly beyond this interface, indicating the significant influence of coastal current to this estuarine environment. The seasonal variation of tryptophan-like C4 was characterized by higher F(max) values in the upper to middle estuary in the dry season, which is in contrast to that of the humic-like C3. Correlation analysis with DOC showed that the fluorescence intensity of Cl (or C2 and C3) was suitable for tracing DOC dynamics in this estuary. These results indicated different mixing behavior and temporal variability for different fluorescent components in this dynamic estuarine environment. (C) 2011 Elsevier B.V. All rights reserved.

关键词： Chromophoric dissolved organic matter Excitation emission matrix fluorescence spectroscopy parallel factor analysis Jiulong Estuary

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Missing data recovery combined with parallel factor analysis model for eliminating Rayleigh scattering in the process of detecting pesticide mixture

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SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020年 232卷 118187页

作者： Wang, Junzhu Wang, Shutao Shang, Fengkai Sun, Yangyang Liu, Shiyu Yanshan Univ Measurement Technol & Instrumentat Key Lab Hebei Qinhuangdao 066004 Hebei Peoples R China

Excitation-Emission Matrix (EEM) fluorescence spectroscopy combined with parallel factor analysis (PARAFAC) provides a widely used method to extract useful information containing unknown components. However, the inherent scattering especially Rayleigh scattering will influence the accuracy of PARAFAC so that appropriate procedure to the scattering becomes an essential problem when processing the EEM data. Many methods have been proposed to solve the problems about eliminating scattering. Missing data recovery combined with PARAFAC model has been discussed in this paper. For EEM data, this method extracted the signal values in the missing area which can effectively correct scattering region. It can eliminate Rayleigh scattering effectively by choosing Gaussian contour constraint. The results of the correlation coefficient (R), the root mean square error of prediction (RMSEP) and average recovery rate (AR) are better which can prove that the combined method is easier to implement and provide better concentration prediction results in detecting pesticide mixture. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Missing data recovery parallel factor analysis Eliminating scattering Detecting pesticide mixture

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Characterization of extracellular polymeric substances in biofilms under long-term exposure to ciprofloxacin antibiotic using fluorescence excitation-emission matrix and parallel factor analysis

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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 2017年第15期24卷 13536-13545页

作者： Gu, Chaochao Gao, Pin Yang, Fan An, Dongxuan Munir, Mariya Jia, Hanzhong Xue, Gang Ma, Chunyan Donghua Univ Coll Environm Sci & Engn 2999 North Renmin Rd Shanghai 201620 Peoples R China Donghua Univ State Environm Protect Engn Ctr Pollut Treatment 2999 North Renmin Rd Shanghai 201620 Peoples R China Univ North Carolina Charlotte Dept Civil & Environm Engn Charlotte NC 28223 USA Chinese Acad Sci Lab Environm Sci & Technol Xinjiang Tech Inst Phys & Chem Urumqi 830011 Peoples R China Chinese Acad Sci Key Lab Funct Mat & Devices Special Environm Urumqi 830011 Peoples R China

The presence of antibiotic residues in the environment has been regarded as an emerging concern due to their potential adverse environmental consequences such as antibiotic resistance. However, the interaction between antibiotics and extracellular polymeric substances (EPSs) of biofilms in wastewater treatment systems is not entirely clear. In this study, the effect of ciprofloxacin (CIP) antibiotic on biofilm EPS matrix was investigated and characterized using fluorescence excitation-emission matrix (EEM) and parallel factor (PARAFAC) analysis. Physicochemical analysis showed that the proteins were the major EPS fraction, and their contents increased gradually with an increase in CIP concentration (0-300 mu g/L). Based on the characterization of biofilm tightly bound EPS (TB-EPS) by EEM, three fluorescent components were identified by PARAFAC analysis. Component C1 was associated with protein-like substances, and components C2 and C3 belonged to humic-like substances. Component C1 exhibited an increasing trend as the CIP addition increased. Pearson's correlation results showed that CIP correlated significantly with the protein contents and component C1, while strong correlations were also found among UV254, dissolved organic carbon, humic acids, and component C3. A combined use of EEM-PARAFAC analysis and chemical measurements was demonstrated as a favorable approach for the characterization of variations in biofilm EPS in the presence of CIP antibiotic.

关键词： Ciprofloxacin Extracellular polymeric substance Biofilm Biological aerated filter Fluorescence excitation-emission matrix parallel factor analysis

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Petroleum contamination characterization and quantification using fluorescence emission-excitation matrices (EEMs) and parallel factor analysis (PARAFAC)

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JOURNAL OF ENVIRONMENTAL ENGINEERING AND SCIENCE 2008年第3期7卷 183-197页

作者： Alostaz, Moh'd Biggar, Kevin Donahue, Robert Hall, Gregory Univ Alberta Dept Civil & Environm Engn CNRL Nat Resources Engn Facil Edmonton AB T6G 2W2 Canada US Coast Guard Acad Dept Sci New London CT 06320 USA

This paper introduces a novel approach to characterize and semi-quantify common petroleum contaminants (natural gas condensate, gasoline, diesel, flare pit residue, and heavy crude oil) and their underlying aromatic hydrocarbon components in solutions based on their fluorescence spectral signatures. The method uses fluorescence excitation-emission matrices (EEMs) combined with multivariate statistical procedures: parallel factor analysis (PARAFAC) and soft independent method of class analogy (SIMCA) to identify the petroleum products. Quantitatively, fluorescence intensities of EEMs of analyzed petroleum products at different concentrations are used to establish standard calibration curves that can be employed to estimate unknown concentrations of similar petroleum products in solutions. As well, underlying aromatic hydrocarbon component concentrations are estimated by performing customized PARAFAC analysis. This approach provides fingerprints for different petroleum products along with estimates of their concentrations in non-fluorescing solvents. Concentrations of predicted PARAFAC components were validated by laboratory chemical analytical results of the same petroleum products.

关键词： petroleum hydrocarbons aromatic fluorescence geo-environmental contamination fluorescence emission-excitation matrices EEMs parallel factor analysis PARAFAC SIMCA

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Underdetermined Blind Source Separation by parallel factor analysis in Time-Frequency Domain

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COGNITIVE COMPUTATION 2013年第2期5卷 207-214页

作者： Yang, Liu Lv, Jun Xiang, Yong S China Univ Technol Sch Elect & Informat Engn Guangzhou 510640 Guangdong Peoples R China Guangdong Univ Technol Fac Automat Guangzhou 510006 Guangdong Peoples R China Deakin Univ Sch Informat Technol Burwood Vic 3125 Australia

This paper presents a new time-frequency approach to the underdetermined blind source separation using the parallel factor decomposition of third-order tensors. Without any constraint on the number of active sources at an auto-term time-frequency point, this approach can directly separate the sources as long as the uniqueness condition of parallel factor decomposition is satisfied. Compared with the existing two-stage methods where the mixing matrix should be estimated at first and then used to recover the sources, our approach yields better source separation performance in the presence of noise. Moreover, the mixing matrix can be estimated at the same time of the source separation process. Numerical simulations are presented to show the superior performance of the proposed approach to some of the existing two-stage blind source separation methods that use the time-frequency representation as well.

关键词： parallel factor analysis underdetermined blind source separation Wigner-Ville distribution

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Study on the cadmium and copper binding characteristics of dissolved organic matter released from human-feces-biochar (HFDOM) using parallel factor analysis (PARAFAC) and two-dimensional correlation spectroscopy (2D-COS)

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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH 2023年第16期30卷 46900-46912页

作者： Chen, Ke Yang, Yanmei Zhao, Hong Jiang, Jinyuan Chinese Res Inst Environm Sci Res Ctr Environm Pollut Control Technol 8 Wai Da Yang Fang Beijing 100012 Peoples R China Chongqing Jiaotong Univ Sch River & Ocean Engn Chongqing 400074 Peoples R China

The benefits of applying manure directly compared to carbonized applications are controversial, and the impact of dissolved organic matter (DOM) released from human feces-based biochar (HFDOM) on the soil environment is not yet known. Comparing the properties of the HFDOM at different pyrolysis temperatures and its binding properties to heavy metals (HMs) can provide some valuable information for the application of human manure-based biochar for soil amendment or HM remediation in soils. The result of EEM-PARAFAC shows that HFDOM contains four components. A comparison of the maximum fluorescence intensity of HFDOM bound to HMs at different pyrolysis temperatures indicates that high pyrolysis temperatures reduce the amount of HFDOM. Upon comparative analysis of 2D-SFS-COS maps, cadmium (Cd(II)) preferentially binds to humic substances and fulvic-like substances at different pyrolysis temperatures (280 degrees C, 380 degrees C), respectively, while copper (Cu(II)) preferentially complexes with fulvic-like substances in both cases. The 2D-FTIR-COS graphs with different pyrolysis temperatures (280 degrees C, 380 degrees C) are observed, and Cd(II) binds preferentially to the C-H stretching (peak 3030 cm(-1)) of olefins, the C-O stretching vibration, and the O-H bending vibration (peak 1231 cm(-1)) of carboxyl groups, respectively, while Cu(II) binds predominantly to the C-O stretching of alcohols, ethers, and esters (peak 1084 cm(-1)), the C = O stretch of the carboxylic acid (peak 1590 cm(-1)), respectively. The variability of these findings suggests that the pyrolysis temperature exerts a significant influence on the functional groups in HFDOM. Furthermore, the complexation stability constant between Cu(II) and the components decreases as the pyrolysis temperature increases, probably because the pyrolysis temperature changes the content of HFDOM and the distribution of functional groups, but the assessment of the influence still needs to be further investigated.

关键词： Human-feces-biochar Dissolved organic matter parallel factor analysis Two-dimensional correlation spectroscopy

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Pressure effects on aluminium oxidation kinetics using X-ray photoelectron spectroscopy and parallel factor analysis

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SURFACE SCIENCE 1999年第3期440卷 438-450页

作者： Do, T McIntyre, NS Univ Western Ontario Dept Chem London ON N6A 5B7 Canada

The effects of water vapour pressure on oxidation kinetics of aluminium have been studied using X-ray photoelectron spectroscopy (XPS) and three-way parallel factor analysis (PARAFAC). While the first technique is a powerful experimental tool for surface oxidation studies, the PARAFAC technique is a sophisticated analytical tool for analysing XPS data. The XPS Al(2p) and O(1s) core level have been used to follow the oxide film growth on clean surfaces at room temperature as a function of oxidation time (ranging from 1 to 60 min) and pressure of water vapour (ranging from 2.0 x 10(-6) to 6.5 x 10(-4) Pa). The growth of thin oxide films on aluminium surfaces has been found to follow the Cabrera-Mott inverse logarithmic law in all pressure ranges studied. The pressure effects have shown that the defect formation reaction at the oxide film/gas interface is the rate determining process in the aluminium oxidation. The pressure dependence of oxidation kinetics can be explained on the basis of metal vacancies in the defect structure of thin aluminium oxide films. (C) 1999 Published by Elsevier Science B.V. All rights reserved.

关键词： aluminium oxide oxidation parallel factor analysis surface chemical reaction XPS

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H-PARAFAC: Hierarchical parallel factor analysis of Multidimensional Big Data

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IEEE TRANSACTIONS ON parallel AND DISTRIBUTED SYSTEMS 2017年第4期28卷 1091-1104页

作者： Chen, Dan Hu, Yangyang Wang, Lizhe Zomaya, Albert Y. Li, Xiaoli Wuhan Univ State Key Lab Software Engn Wuhan 430072 Peoples R China Collaborat & Innovat Ctr Educ Technol Beijing Peoples R China China Univ Geosci Sch Comp Sci Wuhan 430074 Peoples R China Univ Calif Riverside Sch Comp Sci Riverside CA 92507 USA Univ Sydney Sch Informat Technol Sydney NSW 2006 Australia Beijing Normal Univ Natl Key Lab Cognit Neurosci & Learning Beijing 100875 Peoples R China

It has long been an important issue in various disciplines to examine massive multidimensional data superimposed by a high level of noises and interferences by extracting the embedded multi-way factors. With the quick increases of data scales and dimensions in the big data era, research challenges arise in order to (1) reflect the dynamics of large tensors while introducing no significant distortions in the factorization procedure and (2) handle influences of the noises in sophisticated applications. A hierarchical parallel processing framework over a GPU cluster, namely H-PARAFAC, has been developed to enable scalable factorization of large tensors upon a "divide-and-conquer" theory for parallel factor analysis (PARAFAC). The H-PARAFAC framework incorporates a coarse-grained model for coordinating the processing of sub-tensors and a fine-grained parallel model for computing each sub-tensor and fusing sub-factors. Experimental results indicate that (1) the proposed method breaks the limitation on the scale of multidimensional data to be factorized and dramatically outperforms the traditional counterparts in terms of both scalability and efficiency, e.g., the runtime increases in the order of n(2) when the data volume increases in the order of n(3), (2) H-PARAFAC has potentials in refraining the influences of significant noises, and (3) H-PARAFAC is far superior to the conventional window-based counterparts in preserving the features of multiple modes of large tensors.

关键词： Multi-dimensional data processing factorization big data parallel factor analysis GPGPU

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