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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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Midline2 is overexpressed and a prognostic indicator in human breast cancer and promotes breast cancer

《医学前沿（英文）》 2021年 第15卷 第6期   页码 942-942 doi: 10.1007/s11684-021-0876-z

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Screening of indicator pharmaceuticals and personal care products in landfill leachates: a case study

《环境科学与工程前沿（英文）》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1716-y

摘要：

● A systematic framework was developed to identify i-PPCPs for landfill leachate.

关键词： Landfill leachates     PPCPs     Indicator     Screening criteria     Source-specificity    

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Investigating the role of exiting vehicles and turn indicator usage in gap acceptance at single-lane

Nathan P. BELZ

《结构与土木工程前沿（英文）》 2017年 第11卷 第1期   页码 8-16 doi: 10.1007/s11709-016-0365-7

摘要： Roundabouts are becoming a preferred form of intersection control type due to their safety and capacity benefits. Yield control at roundabout entries inherently reduces fuel consumption and emissions when compared to other conventional intersection types. However, these benefits can be limited by poor driver behavior and judgment when entering the roundabout. This research addresses the nature of gap distributions and use of turn indicators by exiting vehicles at three single-lane roundabouts in Vermont, New York, and Alaska. Presented here is a comparison of vehicle headways measured at two different locations in each roundabout. Rejected headways are analyzed in the context of priority abstaining events when entering drivers yield to vehicles exiting on the same leg of the roundabout suggesting that “true” critical gaps are being overestimated. Results indicate that exiting vehicles, particularly those that do not use their turn indicators when departing from the major-stream of traffic have an influence on the entry decision of drivers on the same approach. This behavior is of particular concern for intersection efficiency (i.e., delay) and sustainability (i.e., excess fuel consumption and emissions). Results prompt the consideration of more consistent guidance on and enforcement of turn indicator use during roundabout negotiations.

关键词： roundabouts     exiting vehicles     turn indicator use     headways    

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Modeling effects of a tidal barrage on water quality indicator distribution in the Severn Estuary

Guanghai GAO, Roger A. FALCONER, Binliang LIN

《环境科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 211-218 doi: 10.1007/s11783-012-0464-1

摘要： In this study, emphasis has focused on assessing the potential hydro-environmental impacts of a barrage across the Severn Estuary, with a numerical model being developed and applied to the estuary to assess the impacts of proposed Severn Barrage on the hydrodynamic, sediment transport and faecal indicator organism distribution within the estuary. The results show that the Severn Barrage has the potential to reduce the tidal currents in a highly dynamic estuary. This leads to the reduction of suspended sediment concentrations, which in turn affects the bacterial transport processes which is highly related to the sediment transport processes.

关键词： water quality indicator     Severn Estuary     numerical model     tidal energy    

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Water environment security indicator system for urban water management

Tian HAO, Pengfei DU, Yun GAO

《环境科学与工程前沿（英文）》 2012年 第6卷 第5期   页码 678-691 doi: 10.1007/s11783-012-0450-7

摘要： Water environment security (WES) is defined in terms of three aspects: first, that it meets basic demands due to industrial and domestic usage; second, that it protects public health from acute and chronic threats; and third, that measures are adopted to ensure sustainable ecological functioning of freshwater resources. Limitations associated with current water environment security indicators in China — including inefficiency in terms of environmental monitoring, inappropriate indicators and parameters that do not take sufficient account of local water characteristics, and a lack of management targets — leads to a failure of effective water management. To achieve better water environment management, a systematic approach, encompassing several steps including establish ideal indicator system and narrow down the scope, screen priority pollutants, identify local characteristics and organize discussion workshop, should be followed to establish a comprehensive water environment indicator system. A case study in Suzhou is included to demonstrate the detailed operational procedures used to assess the risks associated with poor management practices relating to water environment security as well as design an appropriate water environment security indicator system.

关键词： water environment security     supervision and management     monitoring parameter     indicator system     Suzhou    

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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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China’s Agriculture Green Development: from Concept to Actions

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023512

摘要：

● A target-threshold indicator evaluation system is proposed to measure China’s agriculture transformation.

关键词： agricultural transformation     Agriculture Green Development     historical trend     indicator system     theoretical conception    

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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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Insight into fluorescence properties of 14 selected toxic single-ring aromatic compounds in water: Experimental

Muhammad Farooq Saleem Khan, Jing Wu, Cheng Cheng, Mona Akbar, Chuanyang Liu, Bo Liu, Jian Shen, Yu Xin

《环境科学与工程前沿（英文）》 2020年 第14卷 第3期 doi: 10.1007/s11783-020-1219-z

摘要： The fluorescence peak location of 14 compounds interpreted at protein-like region. The p-electron system inside aromatic ring contributes to the fluorophore region. Functional group variation effects the emission spectra. Decrease in quantum yield and increase in DE is due to atomic weight F>Cl>Br>I. Theoretically results are in line with experimental ones. Various single-ring aromatic compounds in water sources are of great concern due to its hazardous impact on the environment and human health. The fluorescence excitation-emission matrix (EEMs) spectrophotometry is a useful method to identify organic pollutants in water. This study provides a detailed insight into the fluorescence properties of the 14 selected toxic single-ring aromatic compounds by experimental and theoretical analysis. The theoretical analysis were done with Time-Dependent Density Functional Theory (TD-DFT) and B3LYP/6-31G (d,p) basis set, whereas, Polarizable Continuum Model (PCM) was used to consider water as solvent. The selected compounds displayed their own specific excitation-emission (Ex/Em) wavelengths region, at Ex<280 nm and Em<340 nm, respectively. Whereas the theoretical Ex/Em was observed as, Ex at 240 nm–260 nm and Em at 255 nm–300 nm. Aniline as a strong aromatic base has longer Em (340 nm) than alkyl, carbonyl, and halogens substituted benzenes. The lone pair of electrons at amide substituent serves as a p-electron contributor into the aromatic ring, hence increasing the stability and transition energy, which results in longer emission and low quantum yield for the aniline. The fluorescence of halogenated benzenes illustrates an increase in the HOMO-LUMO energy gap and a decrease in quantum yield associated with atomic size (F>Cl>Br>I). In this study the theoretical results are in line with experimental ones. The understanding of fluorescence and photophysical properties are of great importance in the identification of these compounds in the water.

关键词： Fluorescence     Photophysical properties     Effect of the substituent     Toxic aromatic compounds    

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Cd-tolerant electrochemically active bacteria in MECs toward exotic Cr(VI) based on the sensing of fluorescence

Xia Hou, Liping Huang, Peng Zhou, Hua Xue, Ning Li

《环境科学与工程前沿（英文）》 2018年 第12卷 第4期 doi: 10.1007/s11783-018-1057-4

摘要：

Cell membrane of indigenous Cd-tolerant EAB harbored more cadmium than chromium.

Indigenous Cd-tolerant EAB cytoplasm located more chromium than cadmium.

Simultaneously quantitatively imaging Cd(II) and Cr(III) ions in EAB was achieved.

Current accelerated the harboring of cadmium in EAB at an initial 2 h.

Current directed the accumulation of more chromium in EAB over time.

关键词： Microbial electrolysis cell     Electrochemically active bacteria     Cd-tolerant bacteria     Cd(II) and Cr(VI)     Fluorescence probe    

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Midline2 is overexpressed and a prognostic indicator in human breast cancer and promotes breast cancer

null

《医学前沿（英文）》 2016年 第10卷 第1期   页码 41-51 doi: 10.1007/s11684-016-0429-z

摘要：

Midline2 (MID2) is an ubiquitin-conjugating E2 enzyme linked to tumor progression and a novel interacting partner of breast cancer 1, early-onset (BRCA1). However, the role of MID2 in breast cancer remains unknown. This study investigated the expression, prognostic value, and role of MID2 in breast cancer. The expression of MID2 mRNA and protein was significantly upregulated in breast cancer tissue and established cell lines compared with that in normal breast epithelial cells and paired adjacent non-tumor tissue (P<0.001). Immunohistochemical analysis demonstrated that MID2 was overexpressed in 272 of 284 (95.8%) paraffin-embedded, archived breast cancer tissue. Moreover, MID2 expression increased with advanced clinical stage (P<0.001). High MID2 expression was significantly associated with advanced clinical stages and T, N, and M staging (all P<0.05). Univariate and multivariate analyses indicated that high MID2 expression was an independent prognostic factor for poor overall survival in the entire cohort (93.73 vs. 172.1 months; P<0.001, log-rank test) and in subgroups with stages Tis+ I+ II and III+ IV. Furthermore, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide colony formation, and anchorage-independent growth ability assays were conducted. Results showed that siRNA silencing of MID2 expression significantly reduced MCF-7 and MDA-MB-231 cell proliferation in vitro and blocked the growth of MDA-MB-231 cell xenograft tumors in vivo (P<0.05). This study indicated that MID2 may be a novel prognostic marker and interventional target in breast cancer.

关键词： breast cancer     MID2     proliferation     overall survival     xenograft    

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Synthesis, characterization and fluorescence quenching of conjugated polymer containing triphenylamine

LIU Feng, XIAO Jianhua, REN Weihua, HU Jun, LIU Honglai

《化学科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 428-433 doi: 10.1007/s11705-008-0083-3

摘要： Poly(triphenylamine--phenylenevinylene)s with two different end-groups were obtained through a Wittig polycondensation. The structures of two copolymers were characterized. Ultraviolet and visible spectroscopy (UV-Vis) and photoluminescence (PL) spectra show the end-capped polymer emits intensive green light in both solution and film state. Their applications in the detection of nitro compounds were investigated, and the results show high fluorescence quenching sensitivity of the end-capped polymer towards -nitrotoluene (-NT). When the concentration of -NT was 21.5 × 10 mol/L, the fluorescence quenching reached 96%. Additionally, after the exposure of polymer film in three different quenchers such as dinitrotoluene (DNT), -nitrobenzoquinone (-BQ) and -nitrotoluene (-NT) for 600 s, its fluorescence quenching reached 93.6%, 11.5% and 77.9%, respectively. This kind of polymer has great advantages in preparation and may find applications in the detection of nitro explosives.

关键词： detection     different     fluorescence     UV-Vis     end-capped polymer    

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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

Midline2 is overexpressed and a prognostic indicator in human breast cancer and promotes breast cancer

期刊论文

Screening of indicator pharmaceuticals and personal care products in landfill leachates: a case study

期刊论文

Investigating the role of exiting vehicles and turn indicator usage in gap acceptance at single-lane

Nathan P. BELZ

期刊论文

Modeling effects of a tidal barrage on water quality indicator distribution in the Severn Estuary

Guanghai GAO, Roger A. FALCONER, Binliang LIN

期刊论文

Water environment security indicator system for urban water management

Tian HAO, Pengfei DU, Yun GAO

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

China’s Agriculture Green Development: from Concept to Actions

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

Insight into fluorescence properties of 14 selected toxic single-ring aromatic compounds in water: Experimental

Muhammad Farooq Saleem Khan, Jing Wu, Cheng Cheng, Mona Akbar, Chuanyang Liu, Bo Liu, Jian Shen, Yu Xin

期刊论文

Cd-tolerant electrochemically active bacteria in MECs toward exotic Cr(VI) based on the sensing of fluorescence

Xia Hou, Liping Huang, Peng Zhou, Hua Xue, Ning Li

期刊论文

Midline2 is overexpressed and a prognostic indicator in human breast cancer and promotes breast cancer

null

期刊论文

Synthesis, characterization and fluorescence quenching of conjugated polymer containing triphenylamine

LIU Feng, XIAO Jianhua, REN Weihua, HU Jun, LIU Honglai

期刊论文