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Polybrominated diphenyl ethers in chicken tissues and eggs from an electronic waste recycling area in southeast China

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Journal of Environmental Sciences 2011年第1期23卷 133-138页

作者： xiaofei qin Zhanfen qin Yan Li Yaxian Zhao Xijuan Xia Shishuai Yan Mi Tian Xingru Zhao Xiaobai Xu Yongjian Yang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China Chinese Research Academy of Environmental Sciences Beijing 100012 China Taizhou No. 1 Middle School Taizhou 318000 China

The levels and distributions of polybrominated diphenyl ethers （PBDEs） in chicken tissues from an electronic waste （e-waste） recycling area in southeast China were investigated. Human dietary intake by local residents via chicken muscle and eggs was estimated. The mean PBDEs concentrations in tissues ranged from 15.2 to 3138.1 ng/g lipid weight （lw） and in egg the concentration was 563.5 ng/g lw. The results showed that the level of total PBDEs （∑PBDEs） in the chicken tissue was 2-3 orders of magnitude higher than those reported in the literature. The large difference of ∑PBDEs concentrations between tissues confirmed that the distribution of PBDEs in tissues depend on tissue-specificity rather than the ＂lipid-compartment＂. BDE-209 was the predominant congener （82.5%- 94.7% of ∑PBDEs） in all chicken tissues except in brain （34.7% of ∑PBDEs）, which indicated that deca-BDE （the major commercial PBDE formulation comprising 65%-70% of total production） was major pollution source in this area and could be bioaccumulated in terrestrial animals. The dietary PBDEs intake of the local residents from chicken muscle and egg, assuming only local bred chickens and eggs were consumed, ranged from 2.2 to 22.5 ng/（*** body weight （bw）） with a mean value of 13.5 ng/（day-kg bw）, which was one order of magnitude higher than the value reported in previous studies for consumption of all foodstuffs.

关键词： polybrominated diphenyl ethers chicken egg bioaccumulation tissue distribution exposure risk

Ecotoxicological effects of mixed pollutants resulted from e-wastes recycling and bioaccumulation of polybrominated diphenyl ethers in Chinese loach(Misgurnus anguillicaudatus)

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Journal of Environmental Sciences 2009年第12期21卷 1695-1701页

作者： qin xiaofei XIA Xijuan LI Yan ZHAO Yaxian YANG Zhongzhi FU Shan TI-AN Mi ZHAO Xingru qin Zhanfen XU Xiaobai YANG Yongjian State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China Taizhou No.1 Middle School Taizhou 318000 China

To understand potential ecotoxicological effects of electrical and electronic equipment waste （e-waste） recycling and polybrominated diphenyl ethers （PBDEs） bioaccumulation in loaches, a semi-field experiment using Chinese loach （Misgurnus anguiUicaudatus） as experimental fish was performed. Larval loaches were kept in net-cage for three months in an e-wastes recycling site and a reference site in Southeastern China. There was significant difference of the survival rate between the loaches from the e-wastes recycling site （27%, 19/70） and from reference site （70%, 49/70）. Histopathological responses were also found in all the livers examined in loaches from the e-wastes recycling site. These results showed that mixed pollutants resulted from e-wastes recycling led to ecotoxicological effects on loaches. The bioaccumulation of polybrominated diphenyl ethers （PBDEs）, the main pollutants in e-waste, in loaches was also studied, the mean concentration of total PBDEs in sediment was 6726.17 ng/g wet weight and in water samples was 4.08 ng/L （dissolved phase）. BDE 209 was the dominant congener in sediment and with relatively high concentration in water. Relatively low concentration of BDE 209 （less than 0.01% of total PBDEs） and high concentration of BDE47 （up to 39.34% of total PBDEs） were detected in loaches.

关键词： e-wastes loach ecotoxicological effects polybrominated diphenyl ethers semi-field experiment

Thyroid disruption by technical decabromodiphenyl ether (DE-83R) at low concentrations in Xenopus laevis

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Journal of Environmental Sciences 2010年第5期22卷 744-751页

作者： xiaofei qin Xijuan Xia Zhongzhi Yang Shishuai Yan Yaxian Zhao Rongguo Wei Yan Li Mi Tian Xingru Zhao Zhanfen qin Xiaobai Xu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China Chinese Research Academy of Environmental Sciences Beijing 100012 China

Decabromodiphenyl ether （decaBDE）,as a flame retardant,is widely produced and *** study the thyroid disruption by technical decaBDE at low concentrations,Xenopus laevis tadpoles were exposed to technical decaBDE mixture DE-83R （1-1000 ng/L） in water from stage 46/47 （free swimming larvae,system of Nieuwkoop and Faber） to stage ***-83R at concentration of 1000 ng/L significantly delayed the time to metamorphosis （presented by forelimb emergence,FLE）.Histological examination showed that DE83R at all tested concentrations caused histological alterations-multilayer follicular epithelial cell and markedly increased follicle size accompanied by partial colloid depletion and increase in the peripheral colloid vacuolation,in thyroid *** tested concentrations of DE-83R also induced a down-regulation of thyroid receptor mRNA *** results demonstrated that technical decaBDE disrupted the thyroid system in *** *** of polybrominated diphenyl ethers （PBDEs）（sum of 39 congeners） in *** indicated that mean concentrations of total PBDEs in *** exposed to 1,10,100,1000 ng/L were 11.0,128.1,412.1,1400.2 ng/g wet weight,*** that PBDEs burden of *** tadpoles was close to PBDEs levels in amphibians as reported in previous studies,our study has raised new concerns for thyroid disruption in amphibians of technical decaBDE at environmentally relevant concentrations.

关键词： decabromodiphenyl ether Xenopus laevis thyroid disruption metamorphosis thyroid hormone receptor

Formation kinetics of polyoxymethylene dimethyl ethers from methylal and trioxane with little water

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Chinese Journal of Chemical Engineering 2021年第5期34卷 139-146页

作者： xiaofei qin Sen Lei Xubin Zhang Chen Cao Feng Xin Honglin Chen Xiaoming Zhang Yachen Yin Guilian Wu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China

Polyoxymethylene dimethyl ethers(CH_(3)-O-(CH_(2)O)_(n)-CH_(3),PODE_(n),n>1)can be added to diesel to reduce air pollution caused by incomplete *** by this need,a cost-effective and efficient synthetic route is presented and investigated by this work for the production of PODE_(n),which are formed from methylal and trioxane with low water content(<10%(mass))over HZSM-5 catalyst in a batch slurry autoclave at the temperature from 353.15 K to 393.15 *** reaction rate laws including the PODE_(n) and byproducts of polyoxymethylene hemiformals(HF_(n)),polyoxymethylene glycols(MG),methanol(MeOH)and methyl formate(MF)are *** rate constants of propagation step(k_(6))and depolymerization step(k_(-6))are assumed independent on polymerization degree of PODE_(n).The rate of reaction is proportional to the content of the catalyst(Wcat)for the catalytic reaction within the scope of the *** kinetic parameters were estimated by combining genetic algorithm and least square regression to fit experimental data *** work is valuable for process optimization and reactor design.

关键词： Fuel additive Polyoxymethylene dimethyl ethers Kinetics HZSM-5

Online identification for permanent magnet synchronous motor based on recursive fixed memory least square method under steady state 36

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Online identification for permanent magnet synchronous motor...

Attention-based efficient robot grasp detection network

第36届中国控制会议

作者： Hao Lu Yunkuan Wang Yong Yuan Jun Zheng Jianhua Hu xiaofei qin Institute of Automation University of Chinese Academy of Sciences University of Chinese Academy of Sciences School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology

ISBN: (纸本)9781538629185

Traditional identification method for permanent magnet synchronous motor could not always guarantee the satisfying accuracy,thus an improved online identification method based on recursive fixed memory least square method is proposed in this paper to solve the problem above.A full rank equation is firstly constructed based on the q-axis voltage model under steady *** the recursive fixed memory least square method is used to identify the electrical parameters including stator resistance,inductance and flux at the same *** the fluctuation of rotor current,voltage and speed used in the proposed method is small,influence of measurement bias of online identification can be reduced to the least and thus the accuracy of motor identification can be further *** results show that the proposed method can achieve high accuracy and the identification parameters can converge to the true value quickly.

关键词： permanent magnet synchronous motor full rank the recursive fixed memory least square method online identification

来源： cnki会议评论

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Frontiers of Information Technology & Electronic Engineering 2023年第10期24卷 1430-1444页

作者： xiaofei qin Wenkai HU Chen XIAO Changxiang HE Songwen PEI Xuedian ZHANG School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China College of Science University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Key Laboratory of Modern Optical System Shanghai 200093China Key Laboratory of Biomedical Optical Technology and Devices of Ministry of Education Shanghai 200093China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 201210China

To balance the inference speed and detection accuracy of a grasp detection algorithm,which are both important for robot grasping tasks,we propose an encoder–decoder structured pixel-level grasp detection neural network named the attention-based efficient robot grasp detection network(AE-GDN).Three spatial attention modules are introduced in the encoder stages to enhance the detailed information,and three channel attention modules are introduced in the decoder stages to extract more semantic *** lightweight and efficient DenseBlocks are used to connect the encoder and decoder paths to improve the feature modeling capability of AE-GDN.A high intersection over union(IoU)value between the predicted grasp rectangle and the ground truth does not necessarily mean a high-quality grasp configuration,but might cause a *** is because traditional IoU loss calculation methods treat the center part of the predicted rectangle as having the same importance as the area around the *** design a new IoU loss calculation method based on an hourglass box matching mechanism,which will create good correspondence between high IoUs and high-quality grasp *** achieves the accuracy of 98.9%and 96.6%on the Cornell and Jacquard datasets,*** inference speed reaches 43.5 frames per second with only about 1.2×10^(6)*** proposed AE-GDN has also been deployed on a practical robotic arm grasping system and performs grasping *** are available at https://***/robvincen/robot_gradet.

关键词： Robot grasp detection Attention mechanism Encoder-decoder Neural network

Response of PM_(2.5)-bound elemental species to emission variations and associated health risk assessment during the COVID-19 pandemic in a coastal megacity

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Journal of Environmental Sciences 2022年第12期34卷 115-127页

作者： Guochen Wang Kan Huang qingyan Fu Jia Chen Juntao Huo Qianbiao Zhao Yusen Duan Yanfen Lin Fan Yang Wenjie Zhang Hao Li Jian Xu xiaofei qin Na Zhao Congrui Deng Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Shanghai Environmental Monitoring Center Shanghai 200030China Pudong New District Environmental Monitoring Station Shanghai 200122China Chinese Research Academy of Environmental Sciences Beijing 100012China IRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health Fudan UniversityShanghai 200433China Institute of Eco-Chongming(IEC) Shanghai 202162China

The coronavirus(COVID-19)pandemic is disrupting the world from many *** this study,the impact of emission variations on PM_(2.5)-bound elemental species and health risks associated to inhalation exposure has been analyzed based on real-time measurements at a remote coastal site in Shanghai during the *** trace elemental species decreased significantly and displayed almost no diel peaks during the *** the lockdown,they rebounded rapidly,of which V and Ni even exceeded the levels before the lockdown,suggesting the recovery of both inland and shipping *** sources were identified based on receptor *** combustion accounted for more than 70%of the measured elemental concentrations before and during the *** emissions,fugitive/mineral dust,and waste incineration all showed elevated contributions after the *** total non-carcinogenic risk(HQ)for the target elements exceeded the risk threshold for both children and adults with chloride as the predominant species contributing to ***,the total carcinogenic risk(TR)for adults was above the acceptable level and much higher than that for *** incineration was the largest contributor to HQ,while manufacture processing and coal combustion were the main sources of *** control measures were beneficial for lowering the carcinogenic risk while unexpectedly increased the non-carcinogenic *** the perspective of health effects,priorities of control measures should be given to waste incineration,manufacture processing,and coal combustion.A balanced way should be reached between both lowering the levels of air pollutants and their health risks.

关键词： COVID-19 lockdown PM_(2.5)-bound elemental species Source apportionment Health risk Shanghai

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SRM直接瞬时转矩系统抗饱和控制器设计

系统仿真学报 2017年第12期29卷 3160-3166,3175页

作者：秦晓飞刘杰李峰上海理工大学光电信息与计算机工程学院上海200093

在开关磁阻电机直接瞬时转矩控制系统速度外环控制器中存在非线性饱和,控制器的积分控制环节会对误差进行积累并逐渐使误差增大,造成控制器的饱和效应,降低系统的性能,为此在传统速度控制器基础之上提出一种抗饱和自适应PID控制器,该方... 详细信息

在开关磁阻电机直接瞬时转矩控制系统速度外环控制器中存在非线性饱和,控制器的积分控制环节会对误差进行积累并逐渐使误差增大,造成控制器的饱和效应,降低系统的性能,为此在传统速度控制器基础之上提出一种抗饱和自适应PID控制器,该方法通过对控制器输入饱和误差进行积分,并通过自适应系数调整控制器的积分项,保证系统出现饱和超调时,使其快速退饱和,仿真及试验表明该方法可以抑制饱和现象,提高电机速度响应,降低转速脉动,系统稳定性和鲁棒性较好。

关键词：开关磁阻电机直接瞬时转矩抗饱和 PID控制器

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全塑料浮止阀阀口3D数值仿真研究

中国机械工程 2006年第22期17卷 2379-2382页

作者：李宝仁秦小飞余祖耀桂永胜华中科技大学武汉430074 中国舰船研究设计中心武汉430071

运用CFD软件FLUENT对全塑料浮止阀阀口进行3D数值仿真研究,掌握了浮止阀工作过程中阀腔内液体的压力场和速度场的分布情况,由仿真结果计算了作用在阀芯上的平衡力及液动力,分析比较了两种不同流道结构的浮止阀。研究结果可为合理设计浮... 详细信息

运用CFD软件FLUENT对全塑料浮止阀阀口进行3D数值仿真研究,掌握了浮止阀工作过程中阀腔内液体的压力场和速度场的分布情况,由仿真结果计算了作用在阀芯上的平衡力及液动力,分析比较了两种不同流道结构的浮止阀。研究结果可为合理设计浮止阀结构及研究同类元件提供借鉴。

关键词： FLUENT 浮止阀数值模型仿真