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Arsenic species analysis in porewaters and sediments using hydride generation atomic fluorescence spectrometry

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Journal of Environmental Sciences 2006年第5期18卷 995-999页

作者： LIAO meng-xia DENG Tian-long College of Materials Chemistry and Chemical Engineering Chengdu University of Technology Chengdu 610059 China Qinghai Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China

It was observed that the atomic fluorescence emission due to signal during the determination of As（Ⅲ） in the mixture of As（Ⅲ） and As（V） could has a 10% to 40% of fluorescence emission As（V）. Besides, interferes from heavy metals such as Pb（Ⅱ）, Cu（Ⅱ） can cause severe increase of the signals as compared to the insignificant effects caused by Cd（Ⅱ）, Zn（Ⅱ）, Mn（Ⅱ） and Fe（Ⅲ）. On the basis of further studies, the masking agent of 8-hydroxyquinoline was used as an efficient agent to eliminate interference of As（V） emission and the heavy metal of Cu^2＋ and Pb^2＋ in the measurements of arsenic species, After a series standard additions and CRM researches, a sensitive and interference-free analytical procedure was developed for the speciation of arsenic in samples of porewaters and sediments in Poyang Lake, China.

关键词： arsenic speciation 8-hydroxyquinoline porewaters sediments Poyang Lake

Pollution characteristics of 15 gas- and particle-phase phthalates in indoor and outdoor air in Hangzhou

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Journal of Environmental Sciences 2019年第12期31卷 107-119页

作者： Xingzi Ouyang meng xia Xueyou Shen Yu Zhan College of Environmental&Resource Sciences Zhejiang UniversityHangzhouZhejiang 310058China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control HangzhouZhejiang 310058China Department of Environmental Science and Engineering Sichuan UniversityChengduSichuan 610065China

Phthalate esters(PAEs),typical pollutants widely used as plasticizers,are ubiquitous in various indoor and outdoor *** exist in both gas and particle phases,posing risks to human *** the present study,we chose four typical kinds of indoor and outdoor environments with the longest average human residence times to assess the human exposure in Hangzhou,including newly decorated residences,ordinary residences,offices and outdoor *** order to analyze the pollution levels and characteristics of 15 gasand particle-phase PAEs in indoor and outdoor environments,air and particulate samples were collected *** total PAEs concentrations in the four types of environments were 25,396,25,466.8,15,388.8 and 3616.2 ng/m^3,*** and DEP were the most abundant,and DMPP was at the lowest *** variations in the distributions of indoor/outdoor,gas/particle-phase and different molecular weights of PAEs were observed,showing that indoor environments were the main sources of PAEs *** most PAEs tended to exsit in indoor sites and gas-phase,the high-molecular-weight chemicals tended to exist in the particle-phase and were mainly found in *** were more likely adsorbed by small particles,especially for the indoor *** existed a good correlation between the particle matter concentrations and the PAEs *** addition,neither temperature nor humidity had obvious effects on the distributions of the PAEs concentrations.

关键词： Phthalate esters Indoor and outdoor air Gas and particle phase Distribution characteristics Particles

Hydrothermal Synthesis,Crystal Structure and Spectral Characterization of a New Copper Isopolytungstate: [Cu(phen)_3][W_6O_(19)]

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Chinese Journal of Structural Chemistry 2006年第7期25卷 837-843页

作者： meng Fan-xia LIU Kun CHEN Ya-Guang Institute of Polyoxometalate Chemistry Faculty of Chemistry Northeast Normal University Changchun 130024 China

An unusual inorganic-organic hybrid hexatungstate complex [Cu（phen）3][W6O19] 1 （C36H24 CuN6O19W6, Mr= 2011.20） was hydrothermally synthesized and characterized by singlecrystal X-ray diffraction, IR spectrum, UV-VIS spectrum and elemental analyses. This compound crystallizes in the monoclinic system, space group C2/c with a = 19.1005（11）, b = 11.2585（11）, c = 20.2867（15） A, β= 102.177（2）°, V= 4264.4 A^ 3, μ（MoKa） = 16.691 mm^-1, Dc = 3.133 g/cm^3, Z = 4, F（000） = 3628, the final R = 0.0338 and wR = 0.0798 for 4090 observed reflections with I 〉 2σ（I）. The result of structure determination shows that the crystal structure is constructed from [W6O19]^2- cluster anions and [Cu（phen）3]^2＋ complex fragments, which are held together into a three-dimensional network through hydrogen-bonding interactions.

关键词： hydrothermal synthesis tungstates polyoxometalates copper coordination complexes

Two New Iron Coordination Polymers Based on Fe-pyta Chains Incorporating Pyridine-2,4,6-tricarboxylate

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Chemical Research in Chinese Universities 2008年第4期24卷 392-395页

作者： CHEN Zi-yun PENG meng-xia Department of Chemistry Jiaying University Meizhou 514015 P. R. China

Reaction of FeCIz＇6H20, pyridine-2,4,6-tricarboxylic acid（H3pyta） and NaOH in the hydrothermal system at 185 ℃ resulted in the formation of 1D coordination polymer[Fe（Hpyta）（H2O）2]（1） based on Fe-Hpyta chains. When the abpt[abpt=-4-amino-3,5-bis（4-pyridyl）-l,2,4-triazole] ligand was employed in the reaction system, a 3D supramolecular porous network （H2bpt）[Fe（pyta）（H2O）2]·4H2O（2） was obtained. The framework was constructed with negative （Fe-pyta） chains and the positive H3bpt^＋ in situ, formed from the abpt reagent, to form 1D channels filled with guest water molecules via hydrogen-bonds. X-Ray diffraction crystal structure analysis shows that complex 1 crystallized in the monoclinic system, space group C2/c, a=1.1490（5） nm, b=0.9008（4） nm, c=1.0058（5） nm, B=107.254（9）°, V=0.9942（8） nm3, Z=4; and complex 2 crystallizes in the triclinic system, space group P1 with a=0.90392（11） nm, b=0.96027（11 ） nm, c=1.55540（18） nm, a=73.558（2）°,B= 86.126（2）°,r= 68.745（2）°, V=1.2059（2） nm^3 and Z=2.

关键词： Iron(Ⅱ) Coordination polymer Pyridine-2,4,6-tricarboxylate 4-Amino-3,5-bis(4-pyridyl)-1,2,4-triazole Hydrothermal

Two Novel Lanthanide Coordination Polymers with Differently Bridging Pyridine-2,4,6-tricarboxylate Ligand

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Chemical Research in Chinese Universities 2009年第6期25卷 796-800页

作者： CHEN Zi-yun PENG meng-xia Department of Chemistry Jiaying University Meizhou 514015 P. R. China

Two new lanthanide-pyridinetricarboxylic complexes formulated as [Lu（pyta）（H2O）3]（1） and [La（pyta）· （H2O）2]-***2O（2） were synthesized through hydrothermal reactions of LuC13 or La（NO3）y6H2O with pyridine-2,4,6-tricarboxylic acid（H3pyta）, respectively, and characterized by X-ray crystallography. Complex 1 crystal- lized in the monoclinic system with space group P21/n, a=1.01930（12） nm, b=0.73423（9） nm, c=1.45449（17） Mm, β=94.734（2）° V=1.0848（2） nm3, Z=4. Complex 2 crystallized in the monoclinic system with space group P21/c, a=0.68474（8） nm, b=1.20982（15） nm, c=1.36063（17） nm, β=99.823（2）°, V=l.1106（2） nm3, Z=4. The overall structure of complex 1 consists of 2D binuclear Lu2（pyta）4-based grid coordination layers which are further extended into a 3D supramolecular architecture via hydrogen bonding interactions. With different coordination modes of the pyta ligand, complex 2 is a 3D porous network comprised of La-carboxylate framework.

关键词： Pyridine-2,4,6-tricarboxylic acid Lu(Ⅲ) La(Ⅲ) Hydrothermal method

TICKET attracts pollen tubes and mediates reproductive isolation between relative species in Brassicaceae

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Science China(Life Sciences) 2019年第11期62卷 1413-1419页

作者： Jiang-Guo meng meng-xia Zhang Wei-Cai Yang Hong-Ju Li State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Collage of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China

In flowering plants,pollen tubes are attracted to the ovule by secreted peptides to release the sperm cells for double *** process is species-specific and acts as an important stage of reproductive isolation between *** we identified a cysteine-rich peptide TICKET2 in Arabidopsis thaliana and its orthologs in Arabidopsis lyrata and Capsella rebella that can attract the conspecific pollen tubes,but not the pollen tubes of relative species in *** knockout of the AtTICKET subclade compromised the pollen tube attraction *** study identified a new pollen tube attracting signal and shed light on the molecular basis of reproductive isolation.

关键词： pollen tube attraction peptide attractant reproductive isolation

Flow Behaviour Analysis and Experimental Investigation for Emitter Micro-channels

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Chinese Journal of Mechanical Engineering 2012年第4期25卷 729-737页

作者： WEI Zhengying CAO meng LIU xia TANG Yiping LU Bingheng State Key Lab for Manufacturing System Engineering Xi 'an Jiaotong University Xi 'an 710049 China

The existing research of the flow behavior in emitter micro-channels mainly focuses on the single-phase flow *** the recent micro-particle image velocimetry（PIV） experimental research on the flow characteristics in various micro-channels mainly focuses on the single-phase fluid ***,using an original-size emitter prototype to perform the experiments on the two-phase flow characteristics of the labyrinth channels is seldom *** this paper,the practical flow of water,mixed with sand escaped from filtering,in the labyrinth channel,is *** some research work on the clogging mechanism of the labyrinth channel＇s structure is *** fluid dynamics（CFD） analysis has been performed on liquid-solid two-phase flow in labyrinth-channel *** on flow visualization technology-micro-PIV,the flow in labyrinth channel has been photographed and *** path line graph and velocity vector graph are obtained through the post-treatment of experimental *** graphs agree well with CFD analysis results,so CFD analysis can be used in optimal design of labyrinth-channel *** the optimized anti-clogging structures of the rectangular channel and zigzag channel have been designed *** CFD numerical simulation and the micro-PIV experiments analysis on labyrinth-channel emitter,make the ＂black box＂ of the flow behavior in the emitter channel ***,the proposed research promotes an advanced method to evaluate the emitter＇s performance and can be used to conducting the optimal design of the labyrinth-channel emitters.

关键词： drip irrigation emitter labyrinth channel two-phase flow analysis anti-clogging micro-PIV

Effect of nano-sized precipitates on the crystallography of ferrite in high-strength strip steel

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 448-454页

作者： Jing-jing Yang Run Wu Wen Liang meng-xia Tang Key Laboratory for Ferrous Metallurgy and Resources Utilization of the Ministry of Education Wuhan University of Science and Technology State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology Institute of Research and Design Wuhan Iron and Steel Corporation

For strip steel with the thickness of 1.6 ram, the yield and tensile strengths as high as 760 and 850 MPa, respectively, were achieved using the compact strip production technology. Precipitates in the steel were characterized by scanning and transmission electron microscopy to elucidate the strengthening mechanism. In addition, intragranular misorientation, Kernel average misorientafion, and stored energy were measured using electron backscatter diffraction for crystallographic analysis of ferrite grains containing precipitates and their neighbors without precipitates. It is found that precipitates in specimens primarily consist of TiC and Ti4CzS2. Ferrite grains containing pre- cipitates exhibit the high Taylor factor as well as the crystallographic orientations with {012}, {011}, {112}, or {221} plane parallel to the rolling plane. Compared with the intragranular orientation of adjoining grains, the intragranular misorientation of grains containing precipi- tates fluctuates more frequently and more mildly as a function of distance. Moreover, the precipitates can induce ferrite grains to store a rela- tively large amount of energy. These results suggest that a correlation exists between precipitation in ferrite grains and grain crystallographic properties.

关键词： high strength steel crystallography precipitates hot rolling

Occupational exposure assessment of phthalate esters in indoor and outdoor microenvironments

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Journal of Environmental Sciences 2018年第10期30卷 75-88页

作者： meng xia Xingzi Ouyang Xueqing Wang Xueyou Shen Yu Zhan College of Environmental & Resource Sciences Zhejiang UniversityHangzhou Zhejiang 310058 China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control Hangzhou Zhejiang 310058 China

Phthalate esters（PAEs） are widely used as plasticizers in consumer products. PAEs are a group of environmental hormone which disrupts human and animals＇ endocrine systems. Different occupational groups are exposed to various levels of PAEs. In the present study, four typical occupational groups were chosen, including doctors, college teachers, college students, and drivers who worked in public traffic system. In order to understand the exposure levels to PAEs via inhalation, air samples were collected from multiple microenvironments including indoor and outdoor in Hangzhou to measure the gas and particle concentrations of six PAEs, together with time spent in different microenvironments of these four groups. A comprehensive PAEs exposure model was built to estimate the daily PAEs exposure through inhalation, oral and dermal pathways. The Monte Carlo simulation results show that doctors were exposed to the highest level of PAEs, and consequently had the highest health risk among these four occupational groups. In contrast, college students had the lowest health risk. By setting the exposure level of staying in residences as the baseline, doctors and drivers were two occupations exposed to high PAEs health risk. Di-（2-ethylhexyl） phthalate（DEHP） was the largest contributor among the six phthalates, posing moderate health risk（10-5–10-6） to every occupation. For traffic microenvironments alone, the total exposure levels for different transportation modes were in the descending order of busses, cars, cabs, tubes, motor bikes, and walking.

关键词： Phthalate esters Microenvironment Occupation Exposure assessment Uncertainty analysis