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Occurrence,Spatial Distribution,Sources and Risk Assessment of Per-and Polyfluoroalkyl Substances in Surface Sediments of the Yellow River Delta Wetland

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Journal of Ocean University of China 2024年第5期23卷 1263-1274页

作者： SUN Yu SHEN Nan ZHANG Dahai CHEN Junhui HE Xiuping JI Yinli WANG Haiyang LI xianguo Key Laboratory of Marine Chemistry Theory and Technology(Ocean University of China) Ministry of EducationQingdao 266100China Key Laboratory of Marine Eco-Environmental Science and Technology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Qingdao Key Laboratory of Analytical Technology Development and Offshore Eco-Environment Conservation Qingdao 266061China The Yellow River Delta Sustainable Development Institute of Shandong Province Dongying 257100China

Per-and polyfluoroalkyl substances(PFASs)are emerging persistent organic pollutants(POPs).In this study,47 surface sediment samples were collected from the Yellow River Delta wetland(YRDW)to investigate the occurrence,spatial distribution,potential sources,and ecological risks of ***-three out of 26 targeted PFASs were detected in surface sediment samples from the YRDW,with totalΣ23PFASs concentrations ranging from 0.23 to 16.30 ng g^(-1) dw and a median value of 2.27 ng g^(-1) *** acid(PFOA),perfluorobutanoic acid(PFBA)and perfluorooctanesulfonic acid(PFOS)were the main *** detection frequency and concentration of perfluoroalkyl carboxylic acids(PFCAs)were higher than those of perfluoroal-kanesulfonic acids(PFSAs),while those of long-chain PFASs were higher than those of short-chain *** emerging PFASs substitutes were dominated by 6:2 chlorinated polyfluoroalkyl ether sulfonic acid(6:2 Cl-PFESA).The distribution of PFASs is significantly influenced by the total organic carbon content in the *** concentration of PFASs seems to be related to human activities,with high concentration levels of PFASs near locations such as beaches and *** using a positive matrix factorization model,the potential sources of PFASs in the region were identified as metal plating mist inhibitor and fluoropolymer manufacturing sources,metal plating industry and firefighting foam and textile treatment sources,and food packaging material *** risk assessment indicated that PFASs in YRDW sediments do not pose a significant ecological risk to benthic organisms in the region overall,but PFOA and PFOS exert a low to moderate risk at individual stations.

关键词： per-and polyfluoroalkyl substances Yellow River Delta wetland sediment source identification risk assessment

基于平滑GMS模型和改进扩张状态观测器的复合摩擦补偿

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中国电机工程学报 2024年第5期44卷 1999-2008,I0028页

作者：赵天一贵献国乔岳徐殿国哈尔滨工业大学电气工程及自动化学院黑龙江省哈尔滨市150001

摩擦力是影响直线伺服系统低速运行与点对点定位精度的主要非线性扰动。广义麦克斯韦(generalized Maxwellslip,GMS)摩擦模型虽然可以准确描述摩擦特性用于前馈补偿,但其存在切换点过渡时振荡的问题,同时易受测量噪声和摩擦参数变化等... 详细信息

摩擦力是影响直线伺服系统低速运行与点对点定位精度的主要非线性扰动。广义麦克斯韦(generalized Maxwellslip,GMS)摩擦模型虽然可以准确描述摩擦特性用于前馈补偿,但其存在切换点过渡时振荡的问题,同时易受测量噪声和摩擦参数变化等影响。为此,该文提出基于平滑GMS模型和改进扩张状态观测器(extended state observer,ESO)的复合摩擦补偿策略。首先,引入过渡用双曲正切函数以解决GMS模型中在切换点的反复穿越问题,并给出该模型的离线辨识方法。其次,设计基于模型信息的四阶ESO补偿剩余摩擦力与未知扰动,并引入切比雪夫滤波器整定观测器增益,以降低扰动观测与噪声敏感之间的冲突。为验证所提摩擦补偿策略的有效性,在小型高精度永磁同步直线电机定位平台上进行定位实验。实验结果验证了所提摩擦补偿策略的可行性和有效性。

关键词：永磁同步直线电机摩擦补偿广义麦克斯韦模型过渡函数扩张状态观测器

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Thermosphere joint observations by TM-1 constellations and Swarm-B during the April 2023 geomagnetic storm

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Earth and Planetary Physics 2024年第2期8卷 307-316页

作者： YongPing Li YueQiang Sun xianguo Zhang Jiangzhao Ai XiaoLiang Zheng Jia Li YuJie Wang BiBo Guo Feng Yan ShiLong Wei XinChun Tang YuanYuan Cao National Space Science Center Chinese Academy of SciencesBeijing 100190China Beijing Key Laboratory of Space Environment Exploration Beijing 100190China Key Laboratory of Science and Technology on Space Environment Situational Awareness Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Shenzhen Aerospace Dongfanghong Satellite LtdShenzhen 518057China

The response of thermosphere density to geomagnetic storms is a complicated physical ***-satellite joint observations at the same altitude but different local times(LTs)are important for understanding this process;however,until now such studies have hardly been *** this report,we analyze in detail the thermosphere mass density response at 510 km during the April 23−24,2023 geomagnetic storm using data derived from the TM-1(TianMu-1)satellite constellation and Swarm-B *** observations show that there were significant LT differences in the hemispheric asymmetry of the thermosphere mass density during the geomagnetic *** observed by satellite TM02 at nearly 11.3 and 23.3 LTs were larger in the northern hemisphere than in the *** TM04 dayside density observations appear to be almost symmetrical with respect to the equator,though southern hemisphere densities on the nightside were ***-B data exhibit near-symmetry between the *** addition,the mass density ratio results show that TM04 nightside observations,TM02 data,and Swarm-B data all clearly show stronger effects in the southern hemisphere,except for TM04 on the dayside,which suggest hemispheric *** South-North density enhancement differences in TM02 and TM04 on dayside can reach 130%,and Swarm-B data even achieve 180%*** the observations of all three satellites,large-scale traveling atmospheric disturbances(TADs)first appear at high latitudes and propagate to low latitudes,thereby disturbing the atmosphere above the equator and even into the opposite ***00 model simulations were also performed on this geomagnetic *** are absent in the NRLMSISE00 *** satellite data suggest that NRLMSISE00 significantly underestimates the magnitude of the density response of the thermosphere during geomagnetic storms,especially at high latitudes in both ***,use of the density simulation of NRLM

关键词： TM-1 constellation Swarm-B joint observations geomagnetic storm Local Times

基于Zernike矩与BoF-SURF特征融合的花粉图像分类识别

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计算机工程 2018年第7期44卷 259-263,270页

作者：谢永华朱延刚赵贤国南京信息工程大学计算机与软件学院南京210044 南京信息工程大学江苏省网络监控中心南京210044

针对传统单一花粉图像鉴别特征普遍存在抗噪声干扰能力弱、几何不变性低等问题,提出一种融合Zernike矩全局特征和加速鲁棒性特征包BoF-SURF局部斑点特征的花粉图像分类识别算法。提取花粉图像的Zernike矩描述子以及基于尺度空间梯度信息... 详细信息

针对传统单一花粉图像鉴别特征普遍存在抗噪声干扰能力弱、几何不变性低等问题,提出一种融合Zernike矩全局特征和加速鲁棒性特征包BoF-SURF局部斑点特征的花粉图像分类识别算法。提取花粉图像的Zernike矩描述子以及基于尺度空间梯度信息的SURF特征描述子,使用K-means聚类算法对SURF特征描述子进行特征聚类,构建花粉图像的SURF视觉特征包,并对2种特征进行融合用于花粉图像分类识别。实验结果表明,与传统的花粉图像特征提取算法相比,该算法对花粉尺度和旋转变化具有较好的鲁棒性,在Confocal和Pollenmonitor图像数据集上均获得了较高的识别率。

关键词： Zernike矩目标识别 K-means聚类算法特征融合花粉识别

基于互穿网络技术构筑环境友好型聚合物电解质膜及其电化学性能

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精细化工 2024年第5期41卷 1092-1100页

作者：冉云松陈怡刘阳松赵振强马先果贵州理工学院化学工程学院贵州贵阳550003 贵州省普通高等学校能源化学特色重点实验室贵州贵阳550003

以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为反应型乳化剂,丙烯酸丁酯(BA)、丙烯腈(AN)和丙烯酸(AA)为单体,利用互穿网络技术通过乳液聚合法制备了环境友好型聚合物电解质膜(M-ABAA),采用FTIR、XPS、SEM、TEM和TG对M-ABAA进行了表征;通过CV、... 详细信息

以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为反应型乳化剂,丙烯酸丁酯(BA)、丙烯腈(AN)和丙烯酸(AA)为单体,利用互穿网络技术通过乳液聚合法制备了环境友好型聚合物电解质膜(M-ABAA),采用FTIR、XPS、SEM、TEM和TG对M-ABAA进行了表征;通过CV、EIS和充放电测试考察以M-ABAA为电解质膜组装的CR2032电池的电化学性能。结果表明,当m(AMPS)∶m(BA)∶m(AA)∶m(AN)=1∶3∶2∶2时,制备的M-ABAA(M2)的离子电导率为0.98 mS/cm,抗拉强度为7.53 MPa,断裂伸长率为90.4%,吸液率为150%,热收缩率为4%。M2与目前锂离子电池主流的正负极材料(LiCoO_(2)、LiMn_(2)O_(4)、LiFePO_(4)、NCM811)具有较好的相容性,普适性较好。以M2为电解质隔膜,金属锂为负极,分别以LiCoO_(2)和石墨为正极组装成半电池,0.2 C倍率下的首次放电比容量分别为141.3和347.1 mA·h/g,100圈循环后容量保持率分别为94.8%和85.0%;2.0 C倍率下,放电比容量分别为119.8和239.0 mA·h/g。

关键词：聚合物电解质膜互穿网络技术锂离子电池有机电化学与工业

Survey on the Demand for Elderly Care Services of Community Residents in Beijing and Analysis of Influencing Factors

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Journal of Clinical and Nursing Research 2024年第4期8卷 79-87页

作者： Yue Zhai xianguo Bi Weimin Liu Hong Wang Xinxin Zhang Jing Chen Beijing Century Forum Hospital Capital Medical UniversityBeijing 100038China Beijing Municipal Health Commission Beijing 100053 China Beijing Longfu Hospital Beijing 100010China Yang Song Township Community Health Service Centre Huairou DistrictBeijing 101499China

Objective: To investigate the current situation of the demand for geriatric care services of community residents in Beijing and analyze the influencing factors to provide a reference basis for meeting the demand for diversified and professional geriatric care services. Methods: A self-made questionnaire was used to randomly survey 1558 elderly individuals at community health service centers in 8 urban districts where elderly care centers were planned to be built. The influencing factors of the different characteristics of elderly care service needs from three aspects were analyzed using a dichotomous logistic regression model: predisposing, enabling, and, need factors. Results: 69.7% of the elderly required home care services, 22.8% wanted to get care services at elderly care centers, 15.9% wanted to get care services at nursing homes, 12.3% required community care services, and 7.4% didn’t know where to access care services. 68.5% of the elderly required care services for disabilities/semi-disabilities, 58.0% for dementia, 54.7% for common diseases, 34.9% for rehabilitation training, 33.0% for plumbing care, and 7.5% for hospice care. At the same time, there were urban- rural differences in the demand for elderly care services, with suburban elderly having a higher demand for care services than those living in urban areas (P < 0.05). The elderly’s demand for care services was mainly related to age, place of residence, and gender in the causative factors, mode of residence and physical condition among able factors, and mode of care services and care needs among need factors (P < 0.05). Conclusion: The demand for elderly care services was differentiated by factors including place of residence, age, and gender. It is crucial to accurately match the demand for elderly care services, innovate the mode of elderly care services, and improve the service quality to improve the elderly health service system.

关键词： Elderly care Service system Demand Population ageing Influencing factors

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自动络筒机护纱板圆角加工及抛光工艺

山东纺织科技 2013年第4期54卷 35-37页

作者：徐海艳赵献国青岛宏大纺织机械有限责任公司山东青岛266101

护纱板是络筒机纱路方向控制的重要零件,由于零件与纱线直接接触和相对运动原因,要求其工作表面和护纱周边圆角光滑、圆顺。文章根据自动络筒机护纱板零件的加工特点和加工工艺要求进行了分析和探讨。

关键词：自动络筒机护纱板圆角加工抛光

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基于微电网的分布式光伏发电技术研究

通信电源技术 2023年第20期40卷 26-28页

作者：隋超赵宪国高寿梅国网山东省电力公司沂南县供电公司山东临沂276300

人类社会飞速发展的现阶段,能源紧缺问题越来越突出,因此开发新能源是现如今环境污染与能源紧缺的必然选择。对此,介绍微电网的结构,对微电网的优势进行分析,总结了微电网的推广问题,探讨了基于微电网的分布式光伏发电技术,阐述了分布... 详细信息

人类社会飞速发展的现阶段,能源紧缺问题越来越突出,因此开发新能源是现如今环境污染与能源紧缺的必然选择。对此,介绍微电网的结构,对微电网的优势进行分析,总结了微电网的推广问题,探讨了基于微电网的分布式光伏发电技术,阐述了分布式系统的结构与工作模式、分布式光伏发电系统并网运行中存在的控制问题,提出了基于微电网的分布式光伏发电技术要点,以期能够实现光伏发电结构的合理调整,促进我国可再生能源的可持续发展。

关键词：微电网光伏发电新能源

喷气涡流纺纱机及其关键技术的应用与研究进展

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纺织学报 2024年第3期45卷 209-218页

作者：邵英海赵业平韩贤国曹继鹏张明光陈文辽东学院辽宁丹东118003 福建新华源科技集团有限公司福建福州350200

针对国内外纺纱企业在喷气涡流纺纱机的应用与相关技术的研发情况及其所存在的问题,综述了喷气涡流纺纱机及其关键技术的研究进展,介绍了喷气涡流纺纱机的历史发展及其纺纱系统关键技术,详细分析了喷气涡流纺纱机的导棉喂入、牵伸和输... 详细信息

针对国内外纺纱企业在喷气涡流纺纱机的应用与相关技术的研发情况及其所存在的问题,综述了喷气涡流纺纱机及其关键技术的研究进展,介绍了喷气涡流纺纱机的历史发展及其纺纱系统关键技术,详细分析了喷气涡流纺纱机的导棉喂入、牵伸和输送机构,成纱器,纱线卷绕(横动)、卷装机构等零部件的特征与发展趋势。分析认为:喷气涡流纺纱技术的研究多集中在对现有规模化生产机器的喷气涡流成纱器的结构改进、工作机制探讨上,成果较多且较为成熟,但创新技术不突出;在构建新型成纱器的内部型腔结构和产生更理想的涡流形态上有望进一步突破,以提高喷气涡流纺纱的性能,满足多功能纱线的生产和扩大纺纱应用范围;同时科技进步也使更多智能控制系统的电子清纱器、异纤控制、短线诊断、可视化等技术在纺纱工序中有了应用和发展。

关键词：喷气涡流纺成纱器涡流管导棉机构卷绕机构