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高效液相色谱法检测水环境中全氟辛酸铵的研究

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中国农村水利水电 2024年第8期 54-59,66页

作者：梁佳童薛英文朱玉华武汉大学土木建筑工程学院湖北武汉430072

全氟辛酸铵(APFO)是一种难降解、生物积累和有毒的全氟和多氟烷基化合物(PFAS),对环境和生物健康构成严重威胁。虽然质谱法对PFAS的检测效果较好,但其成本高昂。高效液相色谱(HPLC)法是一种成本较低的检测方法,但现有的技术稳定性、重... 详细信息

全氟辛酸铵(APFO)是一种难降解、生物积累和有毒的全氟和多氟烷基化合物(PFAS),对环境和生物健康构成严重威胁。虽然质谱法对PFAS的检测效果较好,但其成本高昂。高效液相色谱(HPLC)法是一种成本较低的检测方法,但现有的技术稳定性、重现性和效率较低。研究成功建立了一种以高氯酸水溶液和乙腈为流动相能够分离和检测APFO的HPLC法,系统探究了流动相体积比和pH对APFO检测的影响。结果表明,在高氯酸水溶液∶乙腈=60∶40,pH=3.5条件下呈现出最佳的APFO的出峰效果。该方法单样耗费时间少于15 min,检测限为1.01 mg/L,使用更简便的操作和花费更少的时间与成本达到了与其他HPLC方法相近的灵敏度,并在2~50 mg/L的浓度范围具有良好的线性。精密度和准确度实验结果表明,本方法相对标准偏差在9%以内,对实际水体的加标回收率在97.35%~104.80%之间,表现出对复杂样品测定的抗干扰性。本研究展示了该方法在水处理材料开发初期的实验环境中高效且经济地检测高浓度PFAS的巨大潜力。

关键词：高效液相色谱法紫外检测全氟辛酸铵全氟化合物全氟检测

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Numerical investigation of the coupled aero-hydrodynamic performances of a semi-submersible floating offshore wind turbine with inclined columns

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Journal of Hydrodynamics 2024年第2期36卷 316-330页

作者： ying-jie xue Xiao-long Yang Wei-wen Zhao De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Offshore Oil Engineering Co.Ltd. Tianjin300461China

Numerical investigations of floating platforms with different outer column inclined angles under two operating conditions of regular wave and irregular wave are presented in this paper.A coupled aero-hydrodynamic computational fluid dynamics in-house solver FOWT-UALM-SJTU is applied for the ***,the validation for wave and wind generation are conducted to determine mesh distribution *** on these,the hydrodynamic motion response,aerodynamic performance and wake flow are analyzed to explore the impact of inclined *** spectral analysis on the motion response under wave action,discuss the aerodynamic attack angle and inflow wind velocity along the blade spanwise direction in detail,reveal different trends in wake development and *** results show that for the regular wave condition with the increase of inclined angles,the equilibrium position of surge motion is constantly rising,while pitch is *** maximum root mean square(rms)value occurs at angle=30°,compared with the original OC4 FOWT,the rms in power and thrust increase 0.35%,0.71%.And there are two low regions of attack angle and high regions of axial inflow velocity,corresponding to aerodynamic *** spectral analysis indicates that the natural frequency of pitch motion will increase with inclined ***,from the middle to far region of wake flow,the velocity recovery of FOWT with inclined angle will become faster,which is beneficial for downstream turbines to enhance more wind energy.

关键词： Floating offshore wind turbine numerical simulation aero-hydrodynamic coupled analysis floating platform with inclinedcolumns wake flow recovery

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双膜系统净化夏季高温湖水中试

中国给水排水 2024年第11期40卷 49-56页

作者：张增荣陈可延钟燕敏刘志远马永恒张民盛刘博邹春薛英文上海水业设计工程有限公司上海200092 武汉大学土木建筑工程学院湖北武汉430072 上海市政工程设计研究总院<集团>有限公司上海200092

夏季湖水水温高、有机污染物较多,采用常规水处理工艺效果有限,为满足越来越严格的水质标准要求,在武汉市某水厂建立了规模为100 m^(3)/d的双膜(超滤膜+纳滤膜)系统。中试系统进水为该水厂沉淀池或砂滤池出水,分别采用浸没式超滤膜+纳... 详细信息

夏季湖水水温高、有机污染物较多,采用常规水处理工艺效果有限,为满足越来越严格的水质标准要求,在武汉市某水厂建立了规模为100 m^(3)/d的双膜(超滤膜+纳滤膜)系统。中试系统进水为该水厂沉淀池或砂滤池出水,分别采用浸没式超滤膜+纳滤膜工艺和压力式超滤膜+纳滤膜工艺,对比不同双膜系统对水质深度净化的效果。结果表明,双膜系统可以有效去除水中的悬浮物和有机物,针对两种中试进水,纳滤膜可将出水浊度控制在0.10 NTU左右,将UV_(254)控制在0.005cm^(-1)以下,对TDS的去除率在20%~30%左右。当进水为沉后水时,在最优方案中,纳滤膜可将出水CODMn降至0.50 mg/L以下。相较于直接采用超滤膜,臭氧-活性炭预处理工艺+超滤膜处理可以有效降低有机物浓度,缓解纳滤膜污染。混凝+沉淀+臭氧-活性炭预处理+浸没式超滤+纳滤处理工艺对夏季湖水的净化效果更加稳定有效。

关键词：双膜系统夏季湖水超滤膜纳滤膜膜污染

Modification of solid electrolyte interface layer between PVDF-based electrolyte and lithium anode

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Journal of Materiomics 2024年第4期10卷 880-888页

作者： ying Liang Jie Zhang Shundong Guan Kaihua wen Chuangjie Guo Yu-Hsien Wu Haocheng Yuan Sijie Liu ying Qi wenbin Mo xue Zhang Ce-wen Nan State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Qingtao Institute of New Energy Materials Qingtao(Kunshan)Energy Development Co.LtdKunshanJiangsu215300China

Poly(vinylidene fluoride)(PVDF)-based polymer electrolytes(PEs)with good electrochemical performance and processability as well as low-cost advantage,have great potential applications in solid-state lithium(Li)metal batteries(SSLMBs).PVDF-based PEs are generally produced by employing a solution-casting approach with N,N-dimethylformamide(DMF)as the solvent,accompanied by the formation of[DMF-Li^(+)]complex,which facilitates the Li-ion ***,the residual DMF can react continuously with lithium(Li)metal,thereby deteriorating the interface layer in the middle of the PVDF-based PEs and Li ***,we introduce propylene carbonate(PC)into the PVDF-based PEs to regulate the solvation structure and stabilize the interface layer between the PEs and Li *** accelerates the dissociation of lithium oxalyldifluoroborate(LiODFB).Consequently,“lithium propylene dicarbonate(LPDC)‒B-O”oligomer forms as the interfacial layer with high tenacity,homogeneity,and densification,which improves the interfacial contact and suppresses the continuous reaction between the residual DMF and Li *** further demonstrate that the PVDF-based PE prepared with DMF-PC mix-solvents shows improved room-temperature ionic conductivity(1.18×10^(-3) S/cm),enhanced stability against electrodes,and superior cycling performance in LiCoO_(2)-based SSLMBs(maintaining 84% of the initial discharge capacity after 300 cycles).

关键词： Solid-state battery Lithium metal Poly(vinylidene fluoride)electrolyte Propylene carbonate SEI layer

Structural Engineering of Hierarchical Magnetic/Carbon Nanocomposites via In Situ Growth for High-Efficient Electromagnetic Wave Absorption

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Nano-Micro Letters 2024年第9期16卷 262-278页

作者： Xianyuan Liu Jinman Zhou ying xue Xianyong Lu Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

Materials exhibiting high-performance electromagnetic wave absorption have garnered considerable scientific and technological attention,yet encounter significant *** new materials and innovative structural design concepts is crucial for expanding the application field of electromagnetic wave ***,hierarchical structure engineering has emerged as a promising approach to enhance the physical and chemical properties of materials,providing immense potential for creating versatile electromagnetic wave absorption ***,an exceptional multi-dimensional hierarchical structure was meticulously devised,unleashing the full microwave attenuation capabilities through in situ growth,selfreduction,and multi-heterogeneous interface *** hierarchical structure features a three-dimensional carbon framework,where magnetic nanoparticles grow in situ on the carbon skeleton,creating a necklace-like ***,magnetic nanosheets assemble within this *** impedance matching was achieved by precisely adjusting component proportions,and intelligent integration of diverse interfaces bolstered dielectric *** obtain Fe_(3)O_(4)-Fe nanoparticles/carbon nanofibers/Al-Fe_(3)O_(4)-Fe nanosheets composites demonstrated outstanding performance with a minimum reflection loss(RLmin)value of−59.3 dB and an effective absorption bandwidth(RL≤−10 dB)extending up to 5.6 GHz at 2.2 *** notable accomplishments offer fresh insights into the precision design of high-efficient electromagnetic wave absorption materials.

关键词： Electromagnetic wave absorption Hierarchical structure In situ growth Self-reduction

Recursive Projected Filter Algorithm with Binary-Valued Observations

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Journal of Systems Science & Complexity 2024年第5期37卷 1832-1860页

作者： ZHANG Xiaoyan WANG ying xue wenchao ZHAO Yanlong Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper focuses on the state estimate for a class of systems with both process noise and measurement noise under binary-valued observations,in which the Gaussian assumption on the predicted density of the state is not required.A recursive projected filter algorithm with time-varying thresholds is constructed to estimate the state under binary-valued *** time-varying thresholds are designed as the prediction value of the measurement,which can provide more information about the system *** convergence property is established with some suitable stability,boundedness and observability *** particular,the estimation error between state and estimate is proved to be asymptotically bounded in the mean-square sense,whose upper bound is related to the variance of process ***,the theoretical results are demonstrated via numerical examples of first-order and high-order systems.

关键词： Binary-valued observations convergence recursive filter time-varying thresholds

A Double-Timescale Reinforcement Learning Based Cloud-Edge Collaborative Framework for Decomposable Intelligent Services in Industrial Internet of Things

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China Communications 2024年第10期21卷 181-199页

作者： Zhang Qiuyang Wang ying Wang xue School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Networking and Switching Technology(Beijing University of Posts and Telecommunications) Beijing 100876China

With the proportion of intelligent services in the industrial internet of things(IIoT)rising rapidly,its data dependency and decomposability increase the difficulty of scheduling computing *** this paper,we propose an intelligent service computing *** the framework,we take the long-term rewards of its important participants,edge service providers,as the optimization goal,which is related to service delay and computing *** the different update frequencies of data deployment and service offloading,double-timescale reinforcement learning is utilized in the *** the small-scale strategy,the frequent concurrency of services and the difference in service time lead to the fuzzy relationship between reward and *** solve the fuzzy reward problem,a reward mapping-based reinforcement learning(RMRL)algorithm is proposed,which enables the agent to learn the relationship between reward and action more *** large time scale strategy adopts the improved Monte Carlo tree search(MCTS)algorithm to improve the learning *** simulation results show that the strategy is superior to popular reinforcement learning algorithms such as double Q-learning(DDQN)and dueling Q-learning(dueling-DQN)in learning speed,and the reward is also increased by 14%.

关键词： computing service edge intelligence industrial internet of things(IIoT) reinforcement learning(RL)

All types of base conversions allowed by base editors

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Science China(Life Sciences) 2024年第2期67卷 431-433页

作者： Shun-Qing Liang wen xue RNA Therapeutics Institute UMass Chan Medical SchoolWorcester 01655USA Department of Molecular Cell and Cancer BiologyUMass Chan Medical SchoolWorcester 01655USA Department of Molecular Medicine UMass Chan Medical SchoolWorcester 01655USA Li Weibo Institute for Rare Diseases Research UMass Chan Medical SchoolWorcester 01655USA

Base editors(BEs) hold great promise as tools for introducing single-base-pair changes in both basic research and therapeutic applications(Rees and Liu,2018).Base editors are composed of a Cas9 nickase fused to a DNA-modifying enzyme,which chemically modifies nucleobases within a specific targeting window near the Cas9-binding site.

关键词： base bases allowed

Rhodium-Catalyzed N-Arylation Addition of Arylboronic Acids to Ketimines

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Chinese Journal of Chemistry 2024年第18期42卷 2243-2248页

作者： xue-Wei Qian Xing-wen Sun Department of Chemistry Fudan University220 Handan RoadShanghai 200433China

Herein,we report rhodium catalyzed N-arylation via addition of arylboronic acids to electron-deficientα-iminoesters which can be prepared in high efficiency by using easily accessible B-carbonyl *** reaction is highly regiospecific to achieve the N-aryl addition efficiently with up to 99%yield under mild *** corresponding product can be further efficiently converted into indoles andaseries of other important building blocks.

关键词： Rhodium catalyzed N-Arylation addition Amines Umpolung Indole C-C coupling