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Excitation-emission matrix (EEM) fluorescence spectroscopy for characterization of organic matter in

Jinlan Yu, Kang Xiao, Wenchao Xue, Yue-xiao Shen, Jihua Tan, Shuai Liang, Yanfen Wang, Xia Huang

《环境科学与工程前沿（英文）》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1210-8

摘要： • Principles and methods for fluorescence EEM are systematically outlined. • Fluorophore peak/region/component and energy information can be extracted from EEM. • EEM can fingerprint the physical/chemical/biological properties of DOM in MBRs. • EEM is useful for tracking pollutant transformation and membrane retention/fouling. • Improvements are still needed to overcome limitations for further studies. The membrane bioreactor (MBR) technology is a rising star for wastewater treatment. The pollutant elimination and membrane fouling performances of MBRs are essentially related to the dissolved organic matter (DOM) in the system. Three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, a powerful tool for the rapid and sensitive characterization of DOM, has been extensively applied in MBR studies; however, only a limited portion of the EEM fingerprinting information was utilized. This paper revisits the principles and methods of fluorescence EEM, and reviews the recent progress in applying EEM to characterize DOM in MBR studies. We systematically introduced the information extracted from EEM by considering the fluorescence peak location/intensity, wavelength regional distribution, and spectral deconvolution (giving fluorescent component loadings/scores), and discussed how to use the information to interpret the chemical compositions, physiochemical properties, biological activities, membrane retention/fouling behaviors, and migration/transformation fates of DOM in MBR systems. In addition to conventional EEM indicators, novel fluorescent parameters are summarized for potential use, including quantum yield, Stokes shift, excited energy state, and fluorescence lifetime. The current limitations of EEM-based DOM characterization are also discussed, with possible measures proposed to improve applications in MBR monitoring.

关键词： excitation-emission matrix (EEM)     dissolved organic matter (DOM)     membrane bioreactor (MBR)     fluorescence indicator     characterization method    

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Chemical identification and genotoxicity analysis of petrochemical industrial wastewater

Jing ZHANG, Shigong WANG, Can WANG, Hongying HU

《环境科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 350-359 doi: 10.1007/s11783-012-0404-0

摘要： The actual harmful effects of industrial wastewater can not be reflected by the conventional water quality index. Therefore, the change in dissolved organic matter and the genetic toxicity of petrochemical wastewater were observed in the current study by examining the wastewater treatment plant of a large petrochemical enterprise in Northwest China. Using XAD-8, MSC, and DA-7 resins, the wastewater was separated into six fractions, namely, hydrophobic acid (HOA), hydrophobic neutral (HOB), hydrophobic alkaline, hydrophilic acid, hydrophilic alkaline, and hydrophilic neutral. Umu-test was used to detect the genetic toxicity of the wastewater samples, and fluorescence spectra were also obtained to examine genetic toxic substances. The results show that wastewater treatment facilities can effectively reduce the concentration of organic matter in petrochemical wastewater ( <0.05). However, the mixing of aniline wastewater can increase the amount of organic carbon ( <0.05) and can overload facilities. This finding shows that the mixed collection and joint treatment of different types of petrochemical wastewater can affect the water quality of the effluent. Particularly, hydrophobic substances can be difficult to remove and account for a relatively large proportion of the effluent. The mixture of aniline wastewater can increase the genetic toxicity of the effluent ( <0.05), and biologic treatment can not effectively decrease the toxicity. Most of the genetic toxicology may exist in the HOA and HOB fractions. Fluorescence spectroscopy also confirms this result, and tryptophan-like substances may play an important role in genetic toxicity.

关键词： dissolved organic matter     resin fraction     genetic toxicity     fluorescence excitation and emission matrix    

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Investigation of fluorescence characterization and electrochemical behavior on the catalysts of nanosized

Chang-Mao HUNG, Wen-Liang LAI, Jane-Li LIN

《环境科学与工程前沿（英文）》 2013年 第7卷 第3期   页码 428-434 doi: 10.1007/s11783-013-0517-0

摘要： This work describes the environmentally friendly technology for oxidation of ammonia (NH ) to form nitrogen at temperatures range from 423K to 673K by selective catalytic oxidation (SCO) over a nanosized Pt-Rh/γ-Al O catalyst prepared by the incipient wetness impregnation method of hexachloroplatinic acid (H PtCl ) and rhodium (III) nitrate (Rh(NO ) ) with γ-Al O in a tubular fixed-bed flow quartz reactor (TFBR). The characterization of catalysts were thoroughly measured using transmission electron microscopy (TEM), three-dimensional excitation-emission fluorescent matrix (EEFM) spectroscopy, UV-Vis absorption, dynamic light-scattering (DLS), zeta potential meter, and cyclic voltammetry (CV). The results demonstrated that at a temperature of 673K and an oxygen content of 4%, approximately 99% of the NH was removed by catalytic oxidation over the nanosized Pt-Rh/γ-Al O catalyst. N was the main product in NH -SCO process. Further, it reveals that the oxidation of NH was proceeds by the over-oxidation of NH into NO, which was conversely reacted with the NH to yield N . Therefore, the application of nanosized Pt-Rh/γ-Al O catalyst can significantly enhance the catalytic activity toward NH oxidation. One fluorescent peak for fresh catalyst was different with that of exhausted catalyst. It indicates that EEFM spectroscopy was proven to be an appropriate and effective method to characterize the Pt clusters in intrinsic emission from nanosized Pt-Rh/γ-Al O catalyst. Results obtained from the CV may explain the significant catalytic activity of the catalysts.

关键词： ammonia (NH3)     nanosized Pt-Rh/γ-Al2O3 catalyst     excitation-emission fluorescent matrix (EEFM)     selective catalytic oxidation (SCO)     tubular fixed-bed reactor (TFBR)    

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Interactions between metal ions and the biopolymer in activated sludge: quantification and effects of system pH value

Yun Zhou, Siqing Xia, Binh T. Nguyen, Min Long, Jiao Zhang, Zhiqiang Zhang

《环境科学与工程前沿（英文）》 2017年 第11卷 第1期 doi: 10.1007/s11783-017-0898-6

摘要： The biopolymer showed two protein-like fluorescence peaks (peaks A and B). Interactions of Pb(II) and biopolymer were quantified at various system pH values. System pH values significantly affect the quenching constant values for both peaks. Peak B plays a more important role in the interactions than peak A. Removal mechanism of metal ions by activated sludge system was further disclosed. The quantification and effects of system pH value on the interactions between Pb(II) and the biopolymer from activated sludge were investigated. The biopolymer had two protein-like fluorescence peaks (Ex/Em= 280 nm/326–338 nm for peak A; Ex/Em= 220–230 nm/324–338 nm for peak B). The fluorescence intensities of peak B were higher than those of peak A. The fluorophores of both peaks could be largely quenched by Pb(II), and the quencher dose for peak B was about half of that for peak A. The modified Stern-Volmer equation well depicted the fluorescence quenching titration. The quenching constant (Ka) values for both peaks decreased with rising system pH value, and then sharply decreased under alkaline conditions. It could be attributed to that the alkaline conditions caused the reduction of available Pb(II) due to the occurrence of Pb(OH)2 sediments. The Ka values of peak B were bigger than those for peak A at the same system pH values. Accordingly, the aromatic protein (peak B) plays the key role in the interactions between metal ions and the biopolymer.

关键词： Metal ions     Biopolymer     Activated sludge     Three-dimensional excitation emission matrix (3D-EEM)     Fluorescence regional integration (FRI) technique     Quantification    

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A chemometric analysis on the fluorescent dissolved organic matter in a full-scale sequencing batch reactor for municipal wastewater treatment

Chen Qian, Wei Chen, Wei-Hua Li, Han-Qing Yu

《环境科学与工程前沿（英文）》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0962-2

摘要： Rapid monitoring of water quality is crucial to the operation of municipal wastewater treatment plants (WWTPs). Fluorescence excitation-emission matrix (EEM) in combination with parallel factor analysis (PARAFAC) has been used as a powerful tool for the characterization of dissolved organic matter (DOM) in WWTPs. However, a recent work has revealed the drawback of PARAFAC analysis, i.e., overestimating the component number. A novel method, parallel factor framework-clustering analysis (PFFCA), has been developed in our earlier work to resolve this drawback of PARAFAC. In the present work, both PARAFAC and PFFCA were used to analyze the EEMs of water samples from a full-scale WWTP from a practical application point of view. The component number and goodness-of-fit from these two methods were compared and the relationship between the relative score change of component and the actual concentration was investigated to evaluate the estimation error introduced by both methods. PFFCA score and actual concentration exhibited a higher correlation coefficient ( = 0.870) compared with PARAFAC ( <0.771), indicating that PFFCA provided a more accurate relative change estimation than PARAFAC. The results suggest that use of PARAFAC may cause confusion in selecting the component number, while EEM-PFFCA is a more reliable alternative approach for monitoring water quality in WWTPs.

关键词： Wastewater treatment plants (WWTPs)     Excitation-emission matrix (EEM)     Parallel factor (PARAFAC)     Parallel factor framework-clustering analysis (PFFCA)    

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Identification of sources, characteristics and photochemical transformations of dissolved organic matter with EEM-PARAFAC in the Wei River of China

《环境科学与工程前沿（英文）》 2021年 第15卷 第5期 doi: 10.1007/s11783-020-1340-z

摘要：

• The source of DOM in surface water and sediment is inconsistent.

关键词： Dissolved organic matter     Parallel factor analysis     Excitation-emission matrices     Photodegradation    

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Approximation of structural damping and input excitation force

Mohammad SALAVATI

《结构与土木工程前沿（英文）》 2017年 第11卷 第2期   页码 244-254 doi: 10.1007/s11709-016-0371-9

摘要： Structural dynamic characteristics are the most significant parameters that play a decisive role in structural damage assessment. The more sensitive parameter to the damage is the damping behavior of the structure. The complexity of structural damping mechanisms has made this parameter to be one of the ongoing research topics. Despite all the difficulties in the modeling of damping, there are some approaches like as linear and nonlinear models which are described as the energy dissipation throughout viscous, material or structural hysteretic and frictional damping mechanisms. In the presence of a mathematical model of the damping mechanisms, it is possible to estimate the damping ratio from the theoretical comparison of the damped and un-damped systems. On the other hand, solving the inverse problem of the input force estimation and its distribution to each SDOFs, from the measured structural responses plays an important role in structural identification process. In this paper model-based damping approximation method and a model-less structural input estimation are considered. The effectiveness of proposed methods has been carried out through analytical and numerical simulation of the lumped mass system and the results are compared with reference data. Consequently, high convergence of the comparison results illustrates the satisfactory of proposed approximation methods.

关键词： structural modal parameters     damping identification method     input excitation force identification     Inverse problem    

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Characterization of the dissolved organic matter in sewage effluent of sequence batch reactor: the impact of carbon source

Jin GUO, Feng SHENG, Jianhua GUO, Xiong YANG, Mintao MA, Yongzhen PENG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 280-287 doi: 10.1007/s11783-011-0336-0

摘要： Dissolved organic matter (DOM) transformation in sequence batch reactor (SBR) fed with carbon sources of different biodegradability was investigated. During the biologic degradation process, the low molecular weight (MW) fraction (<1 kDa) gradually decreased, while the refractory compounds with higher aromaticity were aggregated. Size exclusion chromatography (SEC) and fluorescence of excitation emission matrices (EEM) demonstrated that more biopolymers (polysaccharides or proteins) and humic-like substances were presented in the extracellular polymeric substance (EPS) extracted from the SBR fed with sodium acetate or glucose, while the EPS from SBR fed with slowly biodegradable dissolved organic carbon (DOC) substrate-starch had relatively less biopolymers. Comparing the EfOM in sewage effluent of three SBRs, the effluent from SBR fed with starch is more aromatic. Organic carbon with MW>1 kDa as well as the hydrophobic fraction in DOM gradually increased with the carbon sources changing from sodium acetate to glucose and starch. The DOC fractionation and the EEM all demonstrated that EfOM from the effluent of the SBR fed with starch contained more fulvic acid-like substances comparing with the SBR fed with sodium acetate and glucose.

关键词： effluent organic matter (EfOM)     extracellular polymeric substance (EPS)     molecular weight distribution (MWD)     hydrophobic     hydrophilic     excitation emission matrices (EEM)    

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Synthesis and fluorescence behavior of 2,5-diphenyl-1,3,4-oxadiazole-containing bismaleimides and bissuccinimides

Xin ZHANG, Zichen LI

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 381-387 doi: 10.1007/s11705-013-1359-9

摘要： Bismaleimides bearing 2,5-diphenyl-1,3,4-oxadiazole chromophores at , , position and corresponding saturated bissuccinimides were synthesized. Several synthetic strategies for these bismaleimides were discussed in detail. Almost no or very weak fluorescence was observed for these bismaleimides, however, the bissuccinimides show a strong fluorescence. The effect of molecular geometry on optical behavior and fluorescence quenching mechanism were investigated by UV-vis absorption and fluorescence emission spectroscopy. The electron coupling of ground state of -bismaleimide is stronger than those of - and -bismaleimides. -Bissuccinimide displays increasing fluorescence quantum yields with red shifts of 22–24 nm, compared to -bissuccinimide. Polymerizable C=C bonds play a key role in the intramolecular fluorescence quenching.

关键词： fluorescence     bismaleimide     oxadiazole     succinimide    

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Decellularized extracellular matrix mediates tissue construction and regeneration

《医学前沿（英文）》 2022年 第16卷 第1期   页码 56-82 doi: 10.1007/s11684-021-0900-3

摘要： Contributing to organ formation and tissue regeneration, extracellular matrix (ECM) constituents provide tissue with three-dimensional (3D) structural integrity and cellular-function regulation. Containing the crucial traits of the cellular microenvironment, ECM substitutes mediate cell–matrix interactions to prompt stem-cell proliferation and differentiation for 3D organoid construction in vitro or tissue regeneration in vivo. However, these ECMs are often applied generically and have yet to be extensively developed for specific cell types in 3D cultures. Cultured cells also produce rich ECM, particularly stromal cells. Cellular ECM improves 3D culture development in vitro and tissue remodeling during wound healing after implantation into the host as well. Gaining better insight into ECM derived from either tissue or cells that regulate 3D tissue reconstruction or organ regeneration helps us to select, produce, and implant the most suitable ECM and thus promote 3D organoid culture and tissue remodeling for in vivo regeneration. Overall, the decellularization methodologies and tissue/cell-derived ECM as scaffolds or cellular-growth supplements used in cell propagation and differentiation for 3D tissue culture in vitro are discussed. Moreover, current preclinical applications by which ECM components modulate the wound-healing process are reviewed.

关键词： decellularized extracellular matrix     3D culture     organoids     tissue repair    

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同步发电机励磁系统中PWM控制的仿真研究

贾贵玺,徐伟,郭宝钥,张臣堂

《中国工程科学》 2005年 第7卷 第6期   页码 50-53

摘要：

优良的励磁控制系统不仅可以保证发电机运行的可靠性和稳定性，而且可有效地提髙发电机和电力系统技术指标。同步发电机励磁系统采用了PWM整流技术，实现励磁电流低谐波和励磁功率单元高功率因数转换，提高了发电机供电质量，并用MATLAB对设计系统做出仿真验证，证明该设计对改善发电机输出电压、提高功率单元电能利用率有明显效果。

关键词： PWM     高功率因数     励磁系统     Matlab仿真    

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Perspective of mixed matrix membranes for carbon capture

Shinji Kanehashi, Colin A. Scholes

《化学科学与工程前沿（英文）》 2020年 第14卷 第3期   页码 460-469 doi: 10.1007/s11705-019-1881-5

摘要： Polymeric membrane-based gas separation has found wide applications in industry, such as carbon capture, hydrogen recovery, natural gas sweetening, as well as oxygen enrichment. Commercial gas separation membranes are required to have high gas permeability and selectivity, while being cost-effective to process. Mixed matrix membranes (MMMs) have a composite structure that consists of polymers and fillers, therefore featuring the advantages of both materials. Much effort has been made to improve the gas separation performance of MMMs as well as general membrane properties, such as mechanical strength and thermal stability. This perspective describes potential use of MMMs for carbon capture applications, explores their limitations in fabrication and methods to overcome them, and addresses their performance under industry gas conditions.

关键词： membranes     polymeric     mixed matrix     impurities    

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Synthesis and characterization of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles with two-photon fluorescence

ZHU Xiaoqin, QIAN Ying, LU Zhifeng

《化学科学与工程前沿（英文）》 2007年 第1卷 第4期   页码 381-384 doi: 10.1007/s11705-007-0069-6

摘要： Four novel 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles that exhibit strong two-photon absorption and enhanced two-photon excited fluorescence were designed and synthesized based on push-core-pull-core-push molecules built from embedding electron-transporting 1,3,4-oxadiazole in aromatic conjugated system through Wittig-Horner reaction. Their chemical structures were determined to show trans-vinylene character according to infrared (IR) and H nuclear magnetic resonance (NMR) spectra. A very effective energy transfer from the excited units to the ?-conjugated bridging unit can enhance the two-photon absorption and two-photon fluorescence.

关键词： 2-arylvinyl     trans-vinylene character     effective     fluorescence     push-core-pull-core-push    

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hydrophobic environment triggering reactive fluorescence probe to real-time monitor mitochondrial DNA

《化学科学与工程前沿（英文）》 2022年 第16卷 第1期   页码 92-102 doi: 10.1007/s11705-021-2063-9

摘要： Mitochondrial DNA has a special structure that is prone to damage resulting in many serious diseases, such as genetic diseases and cancers. Therefore, the rapid and specific monitoring of mitochondrial DNA damage is urgently needed for biological recognition. Herein, we constructed an in situ hydrophobic environment-triggering reactive fluorescence probe named MBI-CN. The fluorophore was 2-styrene-1H-benzo[d]imidazole, and malononitrile was introduced as a core into a molecule to initiate the hydrolysis reaction in the specific environment containing damaged mitochondrial DNA. In this design, MBI-CN conjugates to mitochondrial DNA without causing additional damages. Thus, MBI-CN can be hydrolyzed to generate MBI-CHO in an in situ hydrophobic environment with mitochondrial DNA damage. Meanwhile, MBI-CHO immediately emitted a significative fluorescence signal changes at 437 and 553 nm within 25 s for the damaged mitochondria DNA. Give that the specific and rapid response of MBI-CN does not cause additional damages to mitochondrial DNA, it is a potentially effective detection tool for the real-time monitoring of mitochondrial DNA damage during cell apoptosis and initial assessment of cell apoptosis.

关键词： hydrolysis reaction     mitochondrial DNA damage     in situ hydrophobic environment trigger     fluorescence probe     apoptosis    

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Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 298-306 doi: 10.1007/s11705-022-2212-9

摘要： Herein, a reversible pH fluorescent sensor was developed using caffeic acid as the precursor by one-step solvothermal synthesis method. The carbon dots-based sensor (CA-CDs) exhibited pH-dependent increase in fluorescence intensity and showed linear relationship in the range of pH 6.60 and 8.00. Notably, the fluorescence sensor has a reversible response to pH change. Finally, the CA-CDs has been successfully applied for two-photon imaging of the pH in liver and kidney of diabetic mice. Imaging results showed that the pH value in kidney of diabetic mice was lower than that of the normal mice, while the pH value in liver of diabetic mice was almost the same as that of the normal mice. The present study provides a simple analytical method for pH detection suitable for in vivo.

关键词： carbon dots     two-photon imaging     pH     diabetic mice    

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标题 作者 时间 类型 操作

Excitation-emission matrix (EEM) fluorescence spectroscopy for characterization of organic matter in

Jinlan Yu, Kang Xiao, Wenchao Xue, Yue-xiao Shen, Jihua Tan, Shuai Liang, Yanfen Wang, Xia Huang

期刊论文

Chemical identification and genotoxicity analysis of petrochemical industrial wastewater

Jing ZHANG, Shigong WANG, Can WANG, Hongying HU

期刊论文

Investigation of fluorescence characterization and electrochemical behavior on the catalysts of nanosized

Chang-Mao HUNG, Wen-Liang LAI, Jane-Li LIN

期刊论文

Interactions between metal ions and the biopolymer in activated sludge: quantification and effects of system pH value

Yun Zhou, Siqing Xia, Binh T. Nguyen, Min Long, Jiao Zhang, Zhiqiang Zhang

期刊论文

A chemometric analysis on the fluorescent dissolved organic matter in a full-scale sequencing batch reactor for municipal wastewater treatment

Chen Qian, Wei Chen, Wei-Hua Li, Han-Qing Yu

期刊论文

Identification of sources, characteristics and photochemical transformations of dissolved organic matter with EEM-PARAFAC in the Wei River of China

期刊论文

Approximation of structural damping and input excitation force

Mohammad SALAVATI

期刊论文

Characterization of the dissolved organic matter in sewage effluent of sequence batch reactor: the impact of carbon source

Jin GUO, Feng SHENG, Jianhua GUO, Xiong YANG, Mintao MA, Yongzhen PENG

期刊论文

Synthesis and fluorescence behavior of 2,5-diphenyl-1,3,4-oxadiazole-containing bismaleimides and bissuccinimides

Xin ZHANG, Zichen LI

期刊论文

Decellularized extracellular matrix mediates tissue construction and regeneration

期刊论文

同步发电机励磁系统中PWM控制的仿真研究

贾贵玺,徐伟,郭宝钥,张臣堂

期刊论文

Perspective of mixed matrix membranes for carbon capture

Shinji Kanehashi, Colin A. Scholes

期刊论文

Synthesis and characterization of 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles with two-photon fluorescence

ZHU Xiaoqin, QIAN Ying, LU Zhifeng

期刊论文

hydrophobic environment triggering reactive fluorescence probe to real-time monitor mitochondrial DNA

期刊论文

Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

期刊论文