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Journal of Environmental Sciences 2011年第1期23卷 102-107页

作者： Yang Liu Wenhua Tan xingqiang wu Zhongxing wu Gongliang Yu Renhui Li Key Laboratory of Aquatic Biodiversity and Conservation Biology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A water bloom sample collected from Lake Dishui in Shanghai was characterized. The morphological identification showed that Micorcystis wesenbergii and Micorcystis smithii were the main component of the bloom. Five strains of M. smithii were successfully isolated. Their 16S rRNA gene sequences based phylogenetic tree showed that the five strains of M. smithii intermixed with strains of other morphospecies in Microcystis. A fragment of mcy gene encoding for microcystin synthetase was detected in one of the five M. smithii strains （CHAB 2183）, indicating its potential of microcystin production. High performance liquid chromatography analysis confirmed M. smithii CHAB 2183 to produce microcystin-RR as 1550 μg per gram dry weight cells. The present investigation, for the first time, reported the isolated strains of M. smithii and microcystin production from M. smithii.

关键词： Cyanobacteria Microcystis smithii microcystin-RR mcyA 16S rRNA gene

一步式QuEChERS结合超高效液相色谱-质谱法检测豇豆和芒果中22种农药残留

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食品工业科技 2024年第17期45卷 252-261页

作者：仝凯旋夏寒李建勋谢瑜杰吴兴强范春林陈辉中国检验检疫科学研究院北京100176 中国农业科学院农产品加工研究所北京100193

基于超高效液相色谱-串联质谱法(UPLC-MS/MS)建立了豇豆和芒果中22种农药的一步式QuEChERS自动化检测技术,样品经1%乙酸乙腈提取,加入EN萃取盐(无水硫酸镁、氯化钠、柠檬酸三钠、柠檬酸二钠)除水后,使用C18和石墨化碳黑(GCB)净化,经ACQU... 详细信息

基于超高效液相色谱-串联质谱法(UPLC-MS/MS)建立了豇豆和芒果中22种农药的一步式QuEChERS自动化检测技术,样品经1%乙酸乙腈提取,加入EN萃取盐(无水硫酸镁、氯化钠、柠檬酸三钠、柠檬酸二钠)除水后,使用C18和石墨化碳黑(GCB)净化,经ACQUITY UPLC BEH C18色谱柱分离,以0.01%甲酸水溶液(含2 mmol/L甲酸铵)-0.01%甲酸甲醇为流动相,在多重反应监测(MRM)下进行测定。结果表明,22种农药在0.01~25.00μg/L质量浓度范围内线性关系良好,决定系数R2均大于0.994,方法的检出限(LOD,S/N=3)在0.05~2μg/kg范围内,定量限(LOQ,S/N=10)在0.1~5μg/kg范围内,在1倍LOQ、2倍LOQ和10倍LOQ 3个加标水平下进行回收率实验(n=6),豇豆3个水平的平均回收率分别为70.9%~116.6%、71.9%~118.3%、73.7%~113.7%,芒果平均回收率分别为70.2%~114.6%、71.2%~113.7%、74.3%~118.5%,两种基质相对标准偏差均在20%以内。方法成功应用于42批实际样品检测,有33批检出农药残留。该方法有较高的灵敏度和足够自动化,减少了人为操作步骤,适用于22种农药及农药代谢物的同时检测及准确定量。

关键词：一步式QuEChERS 超高效液相色谱-质谱法农药残留豇豆芒果

Spatiotemporal dynamics of cell abundance,colony size and intracellular toxin concentrations of pelagic and benthic Microcystis in Lake Caohai,China

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Journal of Environmental Sciences 2019年第10期31卷 184-196页

作者： Bing Feng Chunbo Wang xingqiang wu Cuicui Tian Meng Zhang Yingying Tian Bangding Xiao Key Laboratory of Algal Biology of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072China Jiangxi Academy of Environmental Sciences Nanchang 330039 China Henan institute of technology Henan 453003 China

Lake Caohai has experienced extensive Microcystis blooms in recent years,and to improve its water quality,the local government carried out a series of water control *** better understand the dynamics of both pelagic and benthic Microcystis and their characteristics in Lake Caohai,we conducted a 1-year investigation from December 2015to December 2016 to gain a seasonal outlook on the distribution and dynamics of cell abundance,colony size and intracellular microcystins(MCs)of *** results indicated that the Microcystis bloom occupied primarily the northeastern region and then moved gradually from lakeshore to lake *** perennial southwesterly winds and the water inflow from northeast to southwest in Lake Caohai determined the spatiotemporal distribution of pelagic *** Microcystis was mainly distributed in the northeastern region in summer,occupied the lake center in autumn and then occupied the southeastern region in winter,determined by the sedimentation of pelagic Microcystis and the death of benthic *** colonies(20-60μm)overwintered more easily in both water column and *** concentrations of intracellular toxin of benthic Microcystis were observed to be significantly higher than those of pelagic *** might be because Microcystis synthesized large amount of MCs to acclimate to an unfavorable benthic *** knowledge on the dynamics of Microcystis expands our understanding of mechanisms underpinning the formation of Microcystis blooms.

关键词： Spatiotemporal dynamics Pelagic Microcystis Benthic Microcystis Cell abundance Colony size Intracellular MCs

一步式QuEChERS-气相色谱-三重四极杆质谱法快速测定风干牦牛肉中15种N-亚硝胺

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色谱 2024年第5期42卷 465-473页

作者：夏寒仝凯旋朱浙辉谢瑜杰吴兴强常巧英张红医范春林陈辉中国检验检疫科学研究院北京100176 河北大学化学与材料科学学院河北保定071002 西藏自治区产品质量监督检验所西藏拉萨850000

建立了一步式QuEChERS自动提取和净化技术结合气相色谱-串联质谱同时测定风干牦牛肉中15种N-亚硝胺的分析方法。样品水化后,经乙腈提取,加入4.0 g MgSO_(4)和1.0 g NaCl除水,经十八烷基硅烷(C_(18))和N-丙基乙二胺(PSA)填料净化,采用DB-... 详细信息

建立了一步式QuEChERS自动提取和净化技术结合气相色谱-串联质谱同时测定风干牦牛肉中15种N-亚硝胺的分析方法。样品水化后,经乙腈提取,加入4.0 g MgSO_(4)和1.0 g NaCl除水,经十八烷基硅烷(C_(18))和N-丙基乙二胺(PSA)填料净化,采用DB-HeavyWAX色谱柱(30 m×0.25 mm×0.25μm)分离15种N-亚硝胺,在多重反应监测(MRM)模式下进行测定,外标法定量。结果表明,15种N-亚硝胺分离性能良好,在0.1~200μg/L范围内线性关系良好,相关系数(r^(2))≥0.999 0;检出限(LOD)为0.05~0.20μg/kg,定量限(LOQ)为0.10~0.50μg/kg;在1倍、2倍和10倍LOQ 3个添加水平下的平均回收率分别为79.4%~102.1%、80.6%~109.5%、83.0%~110.6%,相对标准偏差(RSD)为0.8%~16.0%。应用建立的方法检测2种不同加工工艺的市售样品,其中7种N-亚硝胺类化合物(N-亚硝基二甲胺、N-亚硝基二异丁胺、N-亚硝基二正丁胺、N-亚硝基甲基苯胺、N-亚硝基乙基苯胺、N-亚硝基吡咯烷、N-亚硝基二苯胺)均有不同程度检出,平均含量为0.08~20.18μg/kg,且熟制风干牦牛肉中N-亚硝胺的检出率和平均含量均高于传统生制风干牦牛肉。该方法实现了前处理的自动化,相较于其他传统方法,操作简单,实验效率高,人为影响因素小,检测灵敏度高,适用于风干牦牛肉中15种N-亚硝胺的快速测定,为研究肉制品中N-亚硝胺的测定提供了方法支持。

关键词：一步式QuEChERS 气相色谱-串联质谱 N-亚硝胺风干牦牛肉

Relationship between morphospecies and microcystin-producing genotypes of Microcystis species in Chinese freshwaters

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Journal of Oceanology and Limnology 2021年第5期39卷 1926-1937页

作者： Yang LIU Youxin CHEN Haiyan FANG Hanyang LU xingqiang wu Gongliang YU Shin-ichi NAKANO Renhui LI College of Life Science Henan Normal UniversityXinxiang 453007China Institute of Hydrobiology Chinese Academy of SciencesWuhan 430072China Center for Ecological Research Kyoto UniversityShiga 520-2113Japan College of Life and Environmental Sciences Wenzhou UniversityWenzhou 325000China Journal of Henan Normal University Xinxiang 453007China

Twenty water bodies in China were sampled,and 186 strains of different Microcystis species were isolated,from which eight morpho species were identified and 43 stains containing the mcyB gene were *** analysis based on the mcyB gene indicated that the microcystin(MC)-producing Microcystis in China could be divided into two groups(ⅠandⅡ)and showed significant differences between the two *** maximum sequence similarity was 69.1%.Microcystins(MCs)were measured by high-performance liquid chromatography(HPLC)analysis,and no microcystin-RR(MC-RR)was detected in some strains belonging to GroupⅡ.Compared to other regions of the world,the proportion of Chinese MC-producing was different,and the regional differences were more obvious.A whole-cell polymerase chain reactio(PCR)assay was conducted to analyze the proportion of the mcyB gene in the laboratory cultured and field cultured *** proportion of four morphospecies(***,***,***,and ***)that contained the mcyB gene exceeded 50%in the field cultured sample *** with former studies,*** was the mo st likely morphotype that can produce MCs in the *** study provided new insight of Microcystis hazard assessment and field monitoring.

关键词： Microcystis morphospecies mcyB 16S rDNA microcystin high-performance liquid chromatography(HPLC)

Effects of organic carbon consumption on denitrifier community composition and diversity along dissolved oxygen vertical profiles in lake sediment surface

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Journal of Oceanology and Limnology 2020年第3期38卷 733-744页

作者： HONG Pei GONG Shihao WANG Chunbo SHU Yilin wu xingqiang TIAN Cuicui Oscar Omondi DONDE CAI Pei wu Huaming XIAO Bangding Key Laboratory of Algal Biology of the Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of Sciences Beijing 100049China College of Life Sciences Anhui Normal UniversityWuhu 241000China

At present,the understanding of the dynamics of denitrifiers at different dissolved oxygen(DO)layers under organic carbon consumption within the surface sediments remains *** this study,high-throughput sequencing and quantitative PCR targeting nirS gene were used to analyze the denitrifier abundance dynamics,community composition,and structure for aerobic(DO 0.5-6.9 mg/L),hypoxic-anoxic(DO 0-0.5 mg/L),and anoxic(DO 0 mg/L)layers in surface sediments under organic carbon *** on the analysis of nirS gene abundance,the values of denitrifying bacteria decreased with organic carbon consumption at different DO *** the bacterial species abundance at the genus level were compared between the high-carbon and low-carbon sediments,there was significant increase in 6 out of 36,7 out of 36 and 6 out of 36 genera respectively for the aerobic,hypoxic-anoxic and anoxic *** the other hand,14 out of 36,9 out of 36 and 15 out of 36 genera showed significant decrease in bacterial species abundance respectively for the aerobic,hypoxic-anoxic and anoxic ***,14 out of 36,20 out of 36,and 15 out of 36 genera had no change in bacterial species abundance respectively for the aerobic,hypoxic-anoxic,and anoxic *** indicates that the carbon utilization ability of different denitrifiers on each DO layers was generally different from each *** of denitrifying bacteria also presented significant differences in different DO layers between the high-and low-carbon content sediment ***,under the high-carbon and low-carbon content,the abundance of nirS gene showed a high peak within the hypoxic-anoxic regions,suggesting that this region might be the main distribution area for the denitrifying bacteria within the surface ***,community of unique denitrifiers occurred in different DO layers and the adaptive changes of the denitrifier community followed the organic carbon consumption.

关键词： eutrophic freshwater lake surface sediments dissolved oxygen profi les denitrifier organic carbon consumption

Improved lakeshore sediment microenvironment and enhanced denitrification efficiency by natural solid carbon sources

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International Journal of Sediment Research 2022年第6期37卷 823-832页

作者： Shihao Gong Oscar Omondi Donde Qijia Cai xingqiang wu Kezheng Song Chunbo Wang Pei Hong Bangding Xiao Cuicui Tian Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Environmental Science Egerton University School of Ecology and Environment Anhui Normal University

At present, the high level of nitrate in tailwater of wastewater treatment plants(WWTPs) has continued to cause serious environmental problems. In current study, wood chips and bark, serving as natural solid carbon source(NSCS), were applied to enhance the denitrification capacity of lakeshore sediment to remove superabundant nitrate in tailwater. The results show that NSCS had a positive effect on denitrification process for lakeshore sediment and increased the total phosphorus removal capacity by 212%-601%. Comparatively, wood chips were better in enhancing denitrification ability of lakeshore sediment for a longer time. At the 70 th day, the nitrate elimination(NEL) of the wood chip-sediment integrated system(WSIS) was 20% and 9% higher than the control system(CS) and bark-sediment integrated system(BSIS), respectively. For the WSIS, the microbial activity and the abundance of nicotinamide adenine dinucleotide(NADH) were significantly increased, and the sediment anaerobic zone was rapidly formed,which were conducive to the denitrification of the sediment. At the DNA level, both groups presented an inconsistency in the abundance of functional denitrification genes with the NEL. At the enzyme level,wood chips significantly increased the nitrate and nitrite reductase activities of the sediment, and promoted denitrification. From the perspective of microbial communities, wood chips highly promoted the abundance of norank＿f＿BIrii41 Proteobacteria and Ruminclostridum more than other denitrifying and potential denitrifying bacteria in the process of sediment denitrification enhancement.

关键词： Natural solid carbon source Sediment Denitrification Nitrate elimination

Simultaneous Screening of 733 Pesticide Residues in Fruits and Vegetables by a GC/LC-Q-TOFMS Combination Technique

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Engineering 2020年第4期6卷 432-441页

作者： Guofang Pang Qiaoying Chang Ruobin Bai Chunlin Fan Zijuan Zhang Hongyuan Yan xingqiang wu Chinese Academy of Inspection and Quarantine Beijing 100176China College of Chemistry and Environmental Science Hebei UniversityBaoding 071002China Beijing Uni-Star Inspection Technology Co.Ltd. Beijing 100176China

In this paper,we report the construction of two accurate mass databases and the development of a combination detection method that simultaneously screens for 733 pesticide and chemical contaminant multi-residues via high-throughput liquid chromatography(LC)-and gas chromatography(GC)-quadru pole-time-of-flight mass spectrometry(Q-TOFMS).This work demonstrates that electronic mass spectral standards may replace chemical-source standard materials as references through one sample preparation and the combination of GC/LC-Q-TOFMS *** cutting-edge technique has also replaced multiresidue determination using targeted detection with non-targeted *** pesticide residue types,sensitivity,recovery,and reproducibility of this combination technique are evaluated in eight fruit and vegetable *** technique shows three advantages:①In comparison with the discovery capability of a single technique,the combination technique shows an improvement of 51.1%(GC-QTOFMS)and 39.6%(LC-Q-TOFMS),respectively;②the combination technique can satisfy a screening limit lower than 10μg·kg^-1 and meet the requirements of“uniform standards,”although some of the pesticide residues could be optimized to further improve screening sensitivity;③over 488 pesticides with recoveries between 60%-120%and relative standard deviation(RSD)<20%at a spiked level of 10μg·kg^-1 were detected with the combination technique in eight different *** 2012 to 2017,this combination technique was applied in an investigation to screen pesticide residues from 1384 sampling locations for 38138 batched samples covering 18 categories and 134 types of fruits and vegetables obtained from across the mainland of *** statistical analysis,533 pesticides in 115891 determinations were detected,and the regularity of pesticides in the fruits and vegetables sold on the Chinese market was shown.

关键词： Pesticide multi-residues GC-Q-TOFMS LC-Q-TOFMS Accurate mass database Spectra library Fruits and vegetables

超高效液相色谱-串联质谱法测定蜂王浆中糠氨酸

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质量安全与检验检测 2024年第4期34卷 1-6,16页

作者：史孟杰胡晓楠谢瑜杰崔宗岩常巧英仝凯旋吴兴强范春林陈辉中国检验检疫科学研究院北京100176 天津市食品安全检测技术研究院秦皇岛海关技术中心

应用超高效液相色谱-串联质谱法建立一种适用于蜂王浆中糠氨酸含量的分析方法。样品用10.6 mol/L盐酸在110℃条件下水解24 h,水解后的样品经C18固相萃取柱净化,3 mol/L盐酸洗脱,纯净水1:1稀释,以2 mM甲酸铵水溶液(含0.01%甲酸)和2 mM甲... 详细信息

应用超高效液相色谱-串联质谱法建立一种适用于蜂王浆中糠氨酸含量的分析方法。样品用10.6 mol/L盐酸在110℃条件下水解24 h,水解后的样品经C18固相萃取柱净化,3 mol/L盐酸洗脱,纯净水1:1稀释,以2 mM甲酸铵水溶液(含0.01%甲酸)和2 mM甲酸铵甲醇溶液(含0.01%甲酸)为流动相进行梯度洗脱,ACQUITY BEH C18柱上分离,电喷雾离子源(ESI)正离子模式,多反应监测模式(MRM)检测基质匹配,外标法定量。结果显示,糠氨酸在0.00125~0.07500 mg/L范围内线性关系良好,相关系数(r2)为0.997,方法检出限(LOD)和定量限(LOQ)分别为17μg/kg和50μg/kg。在1倍、2倍和10倍LOQ这3个添加水平下,糠氨酸的平均回收率范围为105.8%~119.4%,相对标准偏差(RSD)为0.4%~4.9%(n=6)。采用本方法对20批蜂王浆中的糠氨酸进行了测定,样品中糠氨酸含量在68.0~311.5μg/kg之间。本方法检出限低、灵敏度高、准确性好,适用于蜂王浆中糠氨酸的测定。

关键词：蜂王浆糠氨酸超高效液相色谱-串联质谱法

基于LabVIEW与凌阳SPCE061A实现串口数据采集

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微计算机信息 2006年第6Z期22卷 23-25页

作者：田会方吴兴强武汉理工大学机电学院

介绍利用凌阳SPCE061A单片机采集数据,Labview作为开发调试平台,二者之间通过串口实现数据通讯的数据采集系统,详细介绍了软硬件实现方案。

关键词： LabVIEW 虚拟仪器 SPCE061A 串口数据采集