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Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

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Journal of Environmental Sciences 2024年第2期136卷 237-247页

作者： Hua Tang Ying Wang Shengling Si Hongli Li David Da Yong chen National Institute of Metrology 18 BeisanhuandongluChaoyang DistrictBeijing 100029China School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China Si Chuan zhong Ce Biao Wu Technology Co.Ltd. Sichuan 610052China Department of Chemistry University of British ColumbiaVancouver V6T 1Z1BCCanada

A method of quantification of perfluorinated compounds(PFCs)from atmospheric particulate matter(APM)is described.A single step pretreatment method,selective pressurized liquid extraction(SPLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment *** effective sorbent was selected to purify the PFCs during SPLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of *** affecting the SPLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were *** optimum conditions were found to be 120℃,10 min,and 3 cycles,***-MS/MS method was developed to obtain the optimal sensitivity specific to *** method detection limits(MDLs)were 0.006 to 0.48 ng/g for the PFCs studied and the linear response range was from 0.1 to 100 ng/*** ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent *** optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target ***,the method was successfully used to measure 16 PFCs in the APM samples collected in Beijing over five years from 2015 to *** is observed that some PFCs follow the trend of total PFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

关键词： Selective pressurized liquid extraction Liquid chromatography-mass spectrometry Perfluorinated compounds Atmospheric particulate matter Pollution control

Ergothioneine and its congeners:anti-ageing mechanisms and pharmacophore

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Protein & Cell 2024年第3期15卷 191-206页

作者： Li chen Liping zhang Xujun Ye zixin Deng Changming zhao Department of Geriatrics Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan 430072China Key Laboratory of Combinatory Biosynthesis and Drug Discovery School of Pharmaceutical SciencesMinistry of EducationWuhan UniversityWuhan 430072China tThese authors contributed equally.

Ergothioneine,Ovothiol,and Selenoneine are sulfur/selenium-containing histidine-derived natural products widely distributed across different *** exhibit significant antioxidant properties,making them as potential lead compounds for promoting *** evidence suggests that Ergothioneine is positively correlated with healthy ageing and *** mechanisms underlying Ergothioneine's regulation of the ageing process at cellular and molecular levels are beginning to be *** this review,we provide an in-depth and extensive coverage of the anti-ageing studies on Ergothioneine and discuss its possible intracellular targeting *** addition,we highlight the recent efforts in elucidating the biosynthetic details for Ergothioneine,Ovothiol,and Selenoneine,with a particular focus on the study of their pharmacophore-forming enzymology.

关键词： Ergothioneine antioxidant anti-ageing longevity biosynthesis enzymology

Study on Dynamic Mechanical Behavior of Al-Mg-Si Alloy

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 454-462页

作者：陶小旺 LIU Jibo LIU Xianbin chen Jianbin WANG Yonggang 汪小锋 Key Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo 315211China Ningbo zhanci New Material Co. Ltd.Ningbo 315338China

The dynamic mechanical behavior of Al-Mg-Si alloy was investigated under different strain rates by mechanical property and microstructure characterization,constitutive behavior analysis and numerical simulation in the present *** the strain rate increases,the yield strength,ultimate tensile strength and elongation increase first,then remain almost constant,and finally *** alloy always exhibits a typical ductile fracture mode,not depending on the strain ***,as the strain rate increases,the number of dimples gradually *** deformation can refine grains,however,the grain structure is slightly affected by the strain *** optimized Johnson-Cook constitutive equation was used to describe the mechanical behavior and obtained by fitting the true stress-strain *** parameter C was described by a function related to the strain *** fitting true stress-strain curves by the JC model agree very well with the experimental true stress-strain *** true stress-strain curves calculated by the finite element numerical simulation agree well with the experimental true stress-strain curves.

关键词： Al-Mg-Si alloy strain rate mechanical property microstructure Johnson-Cook model finite element simulation

通过构筑嵌覆型碳结构提升Nb_(2)O_(5)的储锂性能

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Science China Materials 2021年第5期64卷 1071-1086页

作者：姬青徐隹军杲祥文程亚军王晓艳左秀霞陈政胡斌杰朱锦 Peter G.Bruce 夏永高 Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China The University of Nottingham Ningbo China Ningbo 315100China University of Chinese Academy of Sciences Beijing 100049China Department of Materials University of OxfordParks RdOX13PHOxfordUnited Kingdom Materials Science and Engineering Program and Texas Materials Institute University of Texas at AustinAustinTX 78712USA University of Nottingham University ParkNottingham NG72RDUnited Kingdom The Henry Royce Institute Parks RoadOxford OX13PHUnited Kingdom The Faraday Institution Quad OneBecquerel AvenueHarwell CampusDidcot OX11 OR1United Kingdom Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

嵌入型过渡金属氧化物因具有安全的工作电压、高比容量和快速的嵌锂能力而受到广泛关注.但低本征电导率特性严重影响其作为锂电负极材料的寿命和性能.本文通过简便易行、可规模化放大的二氧化碳热处理方法构筑了具有新型嵌覆型碳结构的N... 详细信息

嵌入型过渡金属氧化物因具有安全的工作电压、高比容量和快速的嵌锂能力而受到广泛关注.但低本征电导率特性严重影响其作为锂电负极材料的寿命和性能.本文通过简便易行、可规模化放大的二氧化碳热处理方法构筑了具有新型嵌覆型碳结构的Nb_(2)O_(5)/C纳米杂化材料.在控制碳含量的前提下,实现了颗粒聚集体内部表面可控碳包覆.以嵌覆型碳结构的Nb_(2)O_(5)/C纳米杂化材料为负极组装的锂离子电池在40 mA g(-1)电流密度下容量可达387 mA hg(-1),而在200 mA g(-1)电流密度下循环500次后,容量保持率在92%以上.采用电化学滴定、差分电化学质谱(DEMS)等方法对嵌覆型五氧化二铌/碳纳米杂化材料脱嵌锂动力学过程以及产气行为进行了研究.本文提出的嵌覆型碳结构有望为高性能嵌入型过渡金属氧化物的结构设计提供参考.

关键词：锂离子电池过渡金属氧化物负极材料储锂性能纳米杂化材料五氧化二铌热处理方法碳结构

In vivo real-time monitoring delayed administration of M2 macrophages to enhance healing of tendon by NIR-II fluorescence imaging

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Nano Research 2024年第5期17卷 4379-4390页

作者： Yuzhou chen Mo chen chengxuan Yu Huizhu Li Liman Sai Nguyen T.K.Thanh Yueming Wang Yan Wo Jian zhang Xing Yang Evgenii L.Guryev Andrei V.zvyagin Hao De Min Tang Shiyi chen Yunxia Li Yuefeng Hao Sijia Feng Jun chen Sports Medicine Institute of Fudan University Department of Sports MedicineHuashan HospitalFudan UniversityShanghai 200040China Department of Orthopedic Surgery Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Department of Bone and Joint Surgery Department of OrthopedicsRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200001China Department of Physics Shanghai Normal UniversityShanghai 200234China Biophysics Group Department of Physics and AstronomyUniversity College LondonLondon WC1E 6BTUK UCL Healthcare Biomagnetic and Nanomaterials Laboratories London W1S 4BSUK Department of Anatomy and Physiology School of MedicineShanghai Jiao Tong UniversityShanghai 200025China Department of Orthopedics Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou 215500China Institute of Biology and Biomedicine Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Mathematical Institute University of OxfordOxford OX26GGUK Institute of Natural Sciences School of MathematicsShanghai Jiao Tong UniversityShanghai 200240China

The administration time is a critical but long-neglected point in cell therapy based on macrophages because the incorrect time of macrophage administration could result in diverse outcomes regarding the same macrophage *** this work,the second near-infrared(NIR-II)fluorescence imaging in vivo tracking of M2 macrophages during a pro-healing therapy in the mice model of rotator cuff injury revealed that the behavior of administrated macrophages was influenced by the timing of their *** delayed cell therapy(DCT)group had a longer retention time of injected M2 macrophages in the repairing tissue than that in the immediate cell therapy(ICT)*** Keller-Segel model and histological analysis further demonstrated that DCT altered the chemotaxis of M2 macrophages and improved the healing outcome of the repaired structure in comparison with *** results offer a possible explanation of previous conflicting results on reparative cell therapy and provoke reconsideration of the timing of these therapies.

关键词： macrophage cell therapy NIR-II in vivo imaging delayed therapy tendon healing

Extraordinary hot extreme in summer 2022 over the Yangtze River basin modulated by the La Nina condition under global warming

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Advances in Climate Change Research 2024年第1期15卷 21-30页

作者： zhen LIAO Yu-Feng YUAN Yang chen Pan-Mao zHAI State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

A widespread and prolonged hot extreme hit the Yangtze River basin in summer 2022,with 300 sites established new temperature records and nearly 96%stations endured more than 40 hot *** the perspective of the combination effect of the global warming and La Nina condition,potential mechanisms of the hot extreme were *** a record-breaking hot extreme was caused by an extremely strong and westward-shifted western Pacific subtropical high(WPSH).The global warming effect contributed primarily to the abnormal hot days in the Yangtze River basin,coupled with the modulation of the La Nina *** sea surface temperature anomaly pattern under La Nina condition favored more convection activities over the western Pacific,encouraging an enhanced and westward-extended *** addition,an observation-based attribution analysis indicates that anthropogenic warming may increase the probability of such extensively persistent hot extremeby1.8 times.

关键词： Hot extreme The Yangtze River basin Global warming Tropical Pacific forcing

Learning Scalable Task Assignment with Imperative-Priori Conflict Resolution in Multi-UAV Adversarial Swarm Defense Problem

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Journal of Systems Science & Complexity 2024年第1期37卷 369-388页

作者： zHAO zhixin chen Jie XIN Bin LI Li JIAO Keming zHENG Yifan School of Electronics and Information Engineering Tongji UniversityShanghai 201804China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 201804China School of Automation Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Autonomous Intelligent Unmanned Systems Beijing 100081China Shanghai Institute of Intelligent Science and Technology Tongji UniversityShanghai 201804China.

The multi-UAV adversary swarm defense(MUASD)problem is to defend a static base against an adversary UAV swarm by a defensive UAV *** the problem into task assignment and low-level interception strategies is a widely used ***-based approaches for task assignment are a promising *** studies on learning-based methods generally assume decentralized decision-making architecture,which is not beneficial for conflict *** contrast,centralized decision-making architecture is beneficial for conflict resolution while it is often detrimental to *** achieve scalability and conflict resolution simultaneously,inspired by a self-attention-based task assignment method for sensor target coverage problem,a scalable centralized assignment method based on self-attention mechanism together with a defender-attacker pairwise observation preprocessing(DAP-SelfAtt)is ***,an imperative-priori conflict resolution(IPCR)mechanism is proposed to achieve conflict-free ***,the IPCR mechanism is parallelized to enable efficient *** validate the algorithm,a variant of proximal policy optimization algorithm(PPO)is employed for training in scenarios of various *** experimental results show that the proposed algorithm not only achieves conflict-free task assignment but also maintains scalability,and significantly improve the success rate of defense.

关键词： Conflict resolution reinforcement learning scalability task assignment.

Photoperiod Mediates the Effects of Temperature and Light Intensity on the Proliferation of Ulva prolifera

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Journal of Ocean University of China 2024年第1期23卷 255-263页

作者： JIANG Jianan YU Yanyan chen Yili LI Yahe XU Nianjun Key Laboratory of Marine Biotechnology of zhejiang Province School of Marine SciencesNingbo UniversityNingbo 315211China

In order to study the complex effects of photoperiod,temperature,and light intensity on the spore maturation and release number of Ulva prolifera,we cultured thalli segment(2–3 mm)under three different photoperiods(L:D=12:12,14:10 and 10:14),temperature(15℃(LT),25℃(MT)and 30℃(HT))and light intensity(100,200 and 400μmol m^(−2)s^(−1),noted as LL,ML and HL,respectively)*** the maturation time,spore release number and chlorophyll fluorescence were *** results suggested that:1)The spore maturation time was accelerated by higher temperature or higher light intensity from 62 h to 36 h,and changes in day length accelerated the spore maturation to a certain extent as compared with 12:12 light/dark cycle;2)Higher light intensity significantly decreased the chlorophyll fluorescence(Fv′/Fm′,NPQ,rETRmax andα)of the mature reproductive segment under 30℃with 12:12 light/dark *** when in the other photoperiods(10:14 and 14:10 conditions),the inhibitory effects of high light intensity were alleviated significantly;3)The optimum condition for the spore maturation and release was 12:12 light/dark cycle,25℃,400μmol m^(−2)s^(−1),with both shorter and longer photoperiod reducing the spore release number;4)Higher light intensity significantly increased the spore release number under 25℃,but these effects were alleviated by 30℃*** study is the first attempt to elucidate the coincidence effects of photoperiod,temperature and light intensity on the reproduction of Ulva,which would help to reveal the mechanism of the rapid proliferation of green tide.

关键词： light intensity maturation photoperiod reproduction temperature Ulva prolifera

Remarkable enhancement of gas selectivity on organosilica hybrid membranes using urea-modulated metal-organic framework nanoparticles

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 83-92页

作者： Yayun zhao Dechuan zhao Chunlong Kong Yichao Lin Xuezhen Wang Liang chen Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China Collaboration Innovation Center for Tissue Repair Material Engineering Technology China West Normal UniversityNanchong 637009China

Metal-organic framework/organosilica hybrid membranes on tubular ceramic substrates have shown great potential for the implementation of membrane technology in practical gas separation projects due to their higher permeance compared to commercial ***,the selectivities of the reported membranes are ***,we have incorporated urea-modulated metal-organic frameworks into organosilica membranes to greatly enhance its separation *** urea-modulated metal-organic frameworks exhibit less-defined edges of crystallographic facets and high defect *** can be well-dispersed in the organosilica layer,which substantially suppresses the interfacial defects between metal-organic frameworks and organosilica,which is beneficial for improving the selectivity of membranes for gas *** results have shown that the enhanced ideal selectivity of H_(2)/CH_(4) was 165 and that of CO_(2)/CH_(4) was 43,with H_(2) permeance of about 1.25×10^(−6) mol·m^(−2)·s^(−1)·Pa^(−1) and CO_(2) permeance of 3.27×10^(−7) mol·m^(−2)·s^(−1)·Pa^(−1) at 0.2 MPa and 25℃.In conclusion,the high level of hybrid membranes can be used to separate H_(2)(or CO_(2))from the binary gas mixture H_(2)/CH_(4)(or CO_(2)/CH_(4)),which is important for gas separation in practical ***,the simple and feasible modulation of metal-organic framework is a promising strategy to tune different metal-organic frameworks for membranes according to the actual demands.

关键词： zIF-8 nanocrystals urea organosilica hybrid membrane enhanced separation performance