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Ecological thresholds of phytoplankton community across environmental gradients in the harmful algal blooms-frequently-occurring,subtropical coastal waters,East China Sea

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Acta Oceanologica Sinica 2021年第6期40卷 100-110页

作者： Ran Ye Chunying Ge Qiong Wang Qing Xu Guofeng Xu Yongkang Yan Mingli Qin Yanhong Cai Yuejun Fei Marine Environmental monitoring centre of Ningbo Ningbo 315012China

Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic *** study provided insights into the relationships concerning ecological thresholds of phytoplankton communities and individual taxon in response to environmental changes in coastal waters of northern Zhejiang Province,East China *** demonstrated that there existed seasonal variations of phytoplankton community ecological thresholds of which spring being higher than those in *** for individual species,Prorocentrum donghaiense and Noctiluca scintillans were identified as the most tolerant and sensitive indicator species in spring and summer,*** exhibited strong indications in response to environmental *** findings highlighted that phytoplankton community structure in this region was stable when environmental gradients were below the thresholds of sensitive species,whereas potential harmful algal blooms may occur when environmental gradients exceeded the thresholds of tolerant species.

关键词： ecological thresholds phytoplankton community environmental gradients indicator species coastal waters of northern Zhejiang Province

Application of deep autoencoder model for structural condition monitoring

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Journal of Systems Engineering and Electronics 2018年第4期29卷 873-880页

作者： PATHIRAGE Chathurdara Sri Nadith LI Jun LI Ling HAO Hong LIU Wanquan Department of Computing Curtin University centre for Infrastructural monitoring and Protection Curtin University

Damage detection in structures is performed via vibra-tion based structural identification. Modal information, such as fre-quencies and mode shapes, are widely used for structural dama-ge detection to indicate the health conditions of civil *** deep learning algorithm that works on a multiple layer neuralnetwork model termed as deep autoencoder is proposed to learnthe relationship between the modal information and structural stiff-ness parameters. This is achieved via dimension reduction of themodal information feature and a non-linear regression against thestructural stiffness parameters. Numerical tests on a symmetri-cal steel frame model are conducted to generate the data for thetraining and validation, and to demonstrate the efficiency of theproposed approach for vibration based structural damage detec-tion.

关键词： auto encoder non-linear regression deep auto en-coder model damage identification vibration structural health monitoring

Phytoplanktonic biogeography in the subtropical coastal waters,East China Sea along intensive anthropogenic stresses: roles of environmental versus spatial factors

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Acta Oceanologica Sinica 2023年第4期42卷 103-113页

作者： Ran Ye Haibo Zhang Yige Yu Qing Xu Dandi Shen Min Ren Lian Liu Yanhong Cai Marine Environmental monitoring centre of Ningbo Ningbo 315012China

Understanding the relative roles of local environmental effects and spatial effects on phytoplankton community is of essential importance to study the biogeography of them at regional scale. However, the determinants that driving the biogeography of phytoplankton communities in the coastal area of northern Zhejiang still remained unclear. We surveyed phytoplankton community compositions in water columns associated with environmental and spatial influences across five subzones that geographically covering this region over four seasons. Diatoms and dinoflagellates were recorded as the main dominant groups and Coscinodiscus oculs-iridis, Coscinodiscus jonesianus, and Skeletonema costatum, were identified as the major abundant species existing in all *** structured environmental conditions, rather than pure spatial or environmental factors, substantially shaped the biogeography of phytoplankton community, with the former mainly comprised of water temperature,dissolved oxygen, phosphate, pH, and salinity, and the latter referring to a non-negligible factor. This study was the first integrated research that combining environmental filtering with spatial factors in structuring phytoplankton communities at a complete tempo-spatial scale. Our results may facilitate to the further study of harmful algal blooms early-warning in this region.

关键词： biogeography of phytoplankton community environmental factors spatial factors coastal area of northern Zhejiang

β-Correction Spectrophotometric Determination of Cadmium with Cadion

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Chinese Journal Of Geochemistry 1995年第1期14卷 93-96页

作者：郜洪文 Huaibei Environmental monitoring centre Anhui Province Huaibei

Cadmium has been determined by β-correction spectrophotometry with cadion,p-nitrobenzenediazoaminoaz-obenzone,and a non-ionic surfactant,tuiton *** real absorbance of a Cd-cadion chelate in the colored solution can be accurately determined and the complex-ratio of cadion with Cd(II) has been worked out to be ***'s law is obeyed over the concentration range of 0-0.20mg/1 cadmium and the detec-tion limit for cadmium is only 0.003mg/*** experimental results are presented with respect to the determination of trace cadmium in wastewaters.

关键词：镉试镉灵分光光度法重金属污染废水示踪作用

Quantification of selected monohydroxy metabolites of polycyclic aromatic hydrocarbons in human urine

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Science China Chemistry 2015年第10期58卷 1579-1584页

作者： Libin Liu Yueping Luo Junping Bi Haifang Li Jin-Ming Lin Key Laboratory of monitoring for Heavy Metal Pollutants Hunan Province Environmental monitoring centre Beijing Key Laboratory of Microanalytical Methods and Instrumentation Department of Chemistry Tsinghua University

An analytical method was developed to quantitatively determine selected monohydroxy metabolites of polycyclic aromatic hydrocarbons(PAHs) in human urine. The procedure included enzymatic hydrolysis to cleave the conjugated metabolites, solid-phase microextraction enrichment, and gas chromatography-mass spectrometry analysis. The method proved to be sensitive enough to detect the selected PAH metabolites in human urine.

关键词： polycyclic aromatic hydrocarbons metabolites human urine solid-phase microextraction GC/MS

Flow Injection Semi-online Preconcentration Graphite Furnace Atomic Absorption Spectrometry for Determination of Cadmium,Copper and Manganese

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Chemical Research in Chinese Universities 2002年第1期18卷 1-7页

作者： ZHANG Yi-hua, WANG Mei-jia, SU Xing-guang, ZHENG Tao, ZHANG Han-qi and JIN Qin-han Department of Chemistry, Jilin University, Changchun 130023, P. R. ChinaCHEN YingJilin Environmental monitoring centre, Changchun 130011, P. R. China Department of Chemistry Jilin University Changchun Changchun 130023 Jilin Environmental monitoring centre Changchun 130011

A micro-flow injection sorbent extraction preconcentration system was combined with a graphite furnace atomic absorption spectrometry that formed an integrated system for the determination of trace amounts of elements. The analytical performances of the prospsed method for determining Cd, Cu and Mn were studied. The analytes were preconcentrated with a thiol resin(Type 190, produced by Nankai University, China) whose active group is -SH. The elements to be determined were preconcentrated onto the column for 60 s and then rinsed with deionized water and eluted with 30 μL of 1 mol/L HCl. The graphite furnace atomic absorption spectrometry(GFAAS) determination of the concentrated analyte was carried out in parallel with the next preconcentration cycle. Enrichment factors 41, 22 and 20 and detection limits(3 σ , n =10) 0.36, 3.8 and 7.0 ng/L for Cd, Cu and Mn, respectively, along with a sampling frequency of 20 h -1 , were obtained with a 60 s loading time at a sample flow rate of 3.5 mL/min. The analytical results for a number of water samples show that the flow-injection semi-online column preconcentration can not only eliminate the effect of some concomitant elements, such as Li, Na, K, Ca and Mg, on the determination of the analyte, but also enhance the sensitivity.

关键词： Flow-injection Semi-online preconcentration Atomic absorption spectrometry,Cadmium,Copper,Manganese

Research on the ecological risk of heavy metals in the soil around a Pb–Zn mine in the Huize County, China

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Chinese Journal Of Geochemistry 2015年第4期34卷 540-549页

作者： Sijin Lu Yanguo Teng Yeyao Wang Jing Wu Jinsheng Wang China National Environmental monitoring centre College of Water Sciences Beijing Normal University

The soil pollution by heavy metals was characterized in the mine tailings and surrounding soils of an old Pb–Zn mine in Huize County. Three hundred and ninety-six samples of agricultural and non-agricultural soil were analyzed for the total metal concentration by acid digestion and sixty-eight selected soil samples were used to determine the chemical fractionation of heavy metals with the modified BCR sequential extraction method. The pollution index of the heavy metals indices for As, Cd, Cr, Cu,Hg, Pb and Zn of non-agricultural soil and agricultural soils in the study area indicated the spreading of heavy metal pollution. Sequential extraction showed that most of Cd existed in an exchangeable form(31.2 %). The available content of Pb, Cu and Zn was mainly distributed in acid extractable fractions and Fe/Mn oxide fractions(27.9, 30 and 27.2 %), and Hg, As and Cr were mainly associated with residual fractions(90.4, 72.9 and 76.8 %). The risks of heavy metals were also evaluated by the risk assessment code(RAC) and potential ecological risk index, respectively. The results of RAC showed a medium and high risk of Cd(45.6 and 54.4 %), medium risk of Zn(100 %), low and medium risk of Cu(41.2 and 58.8 %), largely no risk of Hg(97.1 %), and mainly low risk of As and Pb(92.6and 91.8 %). The range of the potential ecological risk of soil was 58.2–1839.3, revealing a considerably high ecological risk in the study area, most likely related to acid mine drainage and the mining complexes located in the area. The results can be used during the ecological risk screening stage, in conjunction with the total concentrations and metal fractionation values, to better estimate ecological risk.

关键词：土壤重金属污染潜在生态风险铅锌矿山会泽县连续提取法农业土壤中国酸性矿山排水

Regionalization based on spatial and seasonal variation in ground-level ozone concentrations across China

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Journal of Environmental Sciences 2018年第5期30卷 179-190页

作者： Linjun Cheng Shuai Wang Zhengyu Gong Hong Li Qi Yang Yeyao Wang School of Water Resources and Environment China University of Geosciences China National Environmental monitoring Center State Environmental Protection Key Laboratory of Quality Control in Environmental Monitoring Lancaster Environment centre Lancaster University

Owing to the vast territory of China and strong regional characteristic of ozone pollution,it＇s desirable for policy makers to have a targeted and prioritized regulation and ozone pollution control strategy in China based on scientific evidences. It＇s important to assess its current pollution status as well as spatial and temporal variation patterns across *** advances of national monitoring networks provide an opportunity to insight the actions of ozone pollution. Here, we present rotated empirical orthogonal function（REOF）analysis that was used on studying the spatiotemporal characteristics of daily ozone concentrations. Based on results of REOF analysis in pollution seasons for 3 years＇ observations, twelve regions with clear patterns were identified in China. The patterns of temporal variation of ozone in each region were separated well and different from each other, reflecting local meteorological, photochemical or pollution features. A rising trend in annual averaged Eight-hour Average Ozone Concentrations（O3-8 hr） from 2014 to 2016 was observed for all regions, except for the Tibetan Plateau. The mean values of annual and 90 percentile concentrations for all 338 cities were 82.6 ± 14.6 and 133.9 ± 25.8 μg/m3,respectively, in 2015. The regionalization results of ozone were found to be influenced greatly by terrain features, indicating significant terrain and landform effects on ozone spatial correlations. Among 12 regions, North China Plain, Huanghuai Plain, Central Yangtze River Plain, Pearl River Delta and Sichuan Basin were realized as priority regions for mitigation strategies, due to their higher ozone concentrations and dense population.

关键词： Ozone Spatiotemporal variability REOF Regionalizstion

Do concentrations in eggs and liver tissue tell the same story of temporal trends of mercury in high Arctic seabirds?

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Journal of Environmental Sciences 2018年第6期30卷 65-72页

作者： Mark L.Mallory Birgit M.Braune Biology Department Acadia University Environment and Climate Change Canada National Wildlife Research Centre Carleton University

Mercury（Hg） remains a key contaminant of concern in Arctic biota, and monitoring of Hg concentrations in seabird tissues will be an effective approach to track the effects of implementing the Minamata Convention. We examined trends in total Hg（THg） in liver and egg tissues of two Arctic seabirds, thick-billed murres（Uria lomvia） and northern fulmars（Fulmarus glacialis）, between 1976 and 2013 to assess whether both tissues showed similar patterns of Hg change. Hepatic THg was consistently higher than egg THg, and both species had similar egg THg concentrations, but fulmars had higher hepatic THg than *** THg concentrations showed more relative variation through time than *** suggest that egg THg better reflects exposure of birds to THg in local, Arctic prey,whereas liver THg may incorporate longer term, year-round THg exposure. Additional analysis of THg distribution in Arctic seabirds post-laying would help inform interpretation of long-term trends.

关键词： Canada Fulmarus glacialis Northern fulmar Thick-billed murre Uria lomvia